3x+1 Class records calculation progress map
Status of the 3x+1 class record progress as of: Mar 6, 2026.
Intervals are indicated in units of 1,000,000,000,000 (1 E+12 or 1 trillion numbers).
Calculation of a single block of 10,000 units takes approximately 2-4 days on an NVIDIA graphics processor.

All class records found so far can be viewed on the class records page.
This project can only run because of many cooperating contributors.
If you would like to contribute one or more blocks please go to the search page.
Note: the 3x+1 problem is just one of many distributed projects on the internet.
Trajectory of 63,728,127
Progress history
March 6 2026 : All blocks up to 42,100 completed. Ten more class records confirmed.
December 24 2025 : All blocks up to 35,900 completed. Three more class records confirmed.
July 12 2025 : All blocks up to 33,900 completed. One more class record confirmed.
May 18 2025 : All blocks up to 33,100 completed. Three more class records confirmed.
January 5 2025 : All blocks up to 29,500 completed. Seven more class records confirmed.
October 25 2024 : All blocks up to 27,900 completed. Two more class records confirmed.
September 4 2024 : New Delay record (Delay 2456) found by Kevin.
July 20 2024 : All blocks up to 27,100 completed. Two more class records confirmed.
June 3 2024 : All blocks up to 25,460 completed. One more class record confirmed.
March 27 2024 : All blocks up to 25,300 completed. Three more class records confirmed.
Show/Hide earlier milestones
December 2023 : All blocks up to 24,000 completed. Eight more class records confirmed.
May 2023 : All blocks up to 21,000 completed. Nine more class records confirmed.
January 23 2023 : All blocks up to 18,500 completed. Every number up to 64 bits checked. Five class records confirmed.
August 2022 : All blocks up to 16,400 completed. Five class records confirmed.
May 2022 : All blocks up to 15,000 completed. Seven class records confirmed.
May 2022 : New Delay record (Delay 2442) found by Kevin.
March 2022 : All blocks up to 13,480 completed. Five class records confirmed.
February 2022 : New Delay record (Delay 2429) found by Kevin.
January 2022 : All blocks up to 12,300 completed. Six more class records confirmed.
December 2021 : All blocks up to 10,820 completed. Eight class records confirmed.
September 2021 : New Delay record (Delay 2426) found by Kevin.
August 2021 : All blocks up to 9000,000 completed. Six class records confirmed.
July 2021 : All blocks up to 8000,000 completed. Eight class records confirmed.
May 2021 : All blocks up to 6640,000 completed. Twelve class records confirmed.
April 2021 : New Delay record (Delay 2389) found by Kevin.
February 2021 : New Delay record (Delay 2363) found by Kevin.
February 2021 : New Delay record (Delay 2337) found by Volkmar.
January 2021 : All blocks up to 4700,000 completed. Eight class records confirmed.
December 2020 : All blocks up to 3940,000 completed. Eleven class records confirmed.
December 2020 : New Delay record (Delay 2334) found by Kevin.
November 2020 : All blocks up to 2900,000 completed. Delay record 2331 and twelve more class records confirmed
September 2020 : All blocks up to 2300,000 completed. Eleven class records confirmed
September 2020 : All blocks up to 2000,000 completed. Fifteen class records confirmed
August 2020 : All blocks up to 1620,000 completed. Sixteen class records confirmed
July 2020 : All blocks up to 1300,000 completed. 37 class records confirmed
June 30 2020 : New Delay record (Delay 2330) found by Eric.
June 28 2020 : New Delay record (Delay 2286) found by Kevin.
May 30 2020 : New Delay record (Delay 2283) found by Kevin.
May 2020 : All blocks up to 820,000 completed. Sixteen class record confirmed. All class records below 2100 known.
March 2020 : All blocks up to 698,000 completed. Twelve more class records confirmed.
December 2019 : All blocks up to 602,000 completed. Nine class records confirmed.
September 2019 : All blocks up to 561,200 completed. Delay record 2277 and ten more class record confirmed.
May 2019 : All blocks up to 500,000 completed. Delay record 2264 and eight more class records confirmed.
March 2019 : All blocks up to 455,200 completed. Lowest missing class record (2070) and four others confirmed.
December 2018 : All blocks up to 387,000 completed. Delay record 2261 and nine more class records confirmed.
October 2018 : All blocks up to 366,400 completed. Six more class records confirmed.
June 2018 : All blocks up to 346,000 completed. Three more class records confirmed.
December 2017 : All blocks up to 326,500 completed. Five more class records confirmed.
May 2017 : All blocks up to 305,400 completed. 258 reached. Two more class record confirmed.
October 2016 : All blocks up to 280,000 completed. Three class records confirmed.
March 2016 : All blocks up to 275,200 completed. Four more class records confirmed.
March 19 2016 : New Delay Record (Delay 2258) found by Lutz.
December 2015 : All blocks up to 263,350 completed. Four more class records confirmed. 2100 class records known.
July 2015 : All blocks up to 245,500 completed. Five more class records confirmed.
December 2014 : All blocks up to 222,280 completed. Three more class records confirmed.
November 2014 : All blocks up to 213,800 completed. Delay record 2255 and two more class records confirmed.
May 2014 : All blocks up to 203,920 completed. Three class records confirmed.
February 2014 : All blocks up to 194,060 completed. Five class records confirmed. All class records up to 2050 known.
November 2013 : All blocks up to 184,000 completed. Three more class records confirmed
June 2013 : All blocks up to 166,700 completed. Two more class records confirmed.
April 2013 : All blocks up to 165,200 completed. One more class record confirmed.
February 2013 : All blocks up to 160,740 completed. Six more class records confirmed.
November 2012 : All blocks up to 148,800 completed. Five more class records confirmed
May 2012 : All blocks up to 132,360 completed. Five class records confirmed.
January 2012 : All blocks up to 121,500 completed. Final missing class record below 2000 found.
December 2011 : All blocks up to 120,200 completed. One class record confirmed.
October 2011 : All blocks up to 117,000 completed. Three more class record confirmed.
July 2011 : All blocks up to 107,500 completed. Delay record 2254 and three class records confirmed.
April 2011 : All blocks up to 97,080 completed. Delay Record 2091 and two other class records confirmed.
November 2010 : All blocks up to 91,880 completed. Three class records confirmed.
August 2010 : All blocks up to 90,000 completed. Four more class records confirmed.
February 2010 : All blocks up to 82,700 completed. Two class records confirmed.
June 2009 : All blocks up to 76,160 completed. The lowest missing CR (1964) and one other confirmed.
April 2009 : All blocks up to 72,520 completed, passing 256. Three class records confirmed.
February 2009 : All blocks up to 71,020 completed. One more class record confirmed.
December 2008 : All blocks up to 69,740 completed. The lowest missing CR (1951) and two more confirmed.
November 2008 : All blocks up to 67,500 completed. Class record 2000 finally confirmed.
October 2008 : All blocks up to 66,380 completed. Four more class records confirmed.
May 2008 : All blocks up to 61,160 completed. The lowest missing CR (1925) and three others confirmed.
December 2007 : All blocks up to 58,600 completed. Four class records confirmed.
April 2007 : All blocks up to 54,540 completed. Five more class records confirmed.
October 2006 : All blocks up to 50,000 completed. Delay Record 2090 and five class records confirmed.
November 2005 : All blocks up to 46,100 completed. Double of Record 2045 confirmed as Delay Record 2046.
August 2005 : All blocks up to 45,040 completed. Five class records confirmed.
May 2005 : Delay Record of 2090 found at ±46,785 E+12 by Eric
February 2005 : All blocks up to 42,060 completed. Three more class record confirmed.
November 2004 : All blocks up to 40,000 completed. Four class records confirmed.
August 2004 : All blocks up to 37,500 completed. Another four class records confirmed.
May 2004 : All blocks up to 36,120 completed. Seven class records confirmed.
January 2004 : All blocks up to 31,960 completed. Five further class records confirmed.
November 2003 : All blocks up to 29,840 completed. One more class record confirmed.
August 2003 : All blocks up to 29,240 completed. Another fifteen class records confirmed.
April 2003 : All blocks up to 23,100 completed. Delay record 2045 and seven class records confirmed.
December 2002 : All blocks up to 20,100 completed. All class records below 1900 known.
November 2002 : All blocks up to 20,000 completed. Delay record 2042 and fourteen class records confirmed.
November 2002 : Delay Record of 2045 found at ±22,702 E+12 by Kevin
July 2002 : All blocks up to 16,460 completed. Delay record 2039 and fifteen class records confirmed.
April 2002 : All blocks up to 12,720 completed. Another fourteen class records confirmed.
March 2002 : Delay Record of 2042 found at ±17,026 E+12 by Michael
February 2002 : All blocks up to 9340 completed. Two more class records confirmed.
December 2001 : Delay Record of 2039 found at ±12,770 E+12 by Billy
November 2001 : All blocks up to 9020 completed. One Delay record and ten class records confirmed.
September 2001 : All blocks up to 6800 completed. Three Delay records and fourteen class records confirmed. 
August 2001 : All blocks up to 3600 completed. Two Delay records and five class records confirmed
June 2001 : Delay Record of 1958 found at ±7579 E+12 by Kevin
May 2001 : Delay Record of 1919 found at ±6482 E+12 by Kevin
April 2001 : Delay Record of 1916 found at ±4861 E+12 by Kevin
March 2001 : Delay Record of 1903 found at ±4320 E+12 by Kevin
March 2001 : Delay Record of 1895 found at ±3586 E+12 by Eric
March 2001 : Delay Record of 1874 found at ±2978 E+12 by Kevin
February 2001 : All blocks up to 2620 completed. Three class records confirmed.
January 2001 : New Class and Delay Record of 1871 found at 2234,047405,400065.

Range 2000-20000
completed (view)
Range 20000-40000
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Range 40000-60000
completed (view)
Range 60000-80000
completed (view)
Range 80000-100000
completed (view)
Range 100000-120000
completed (view)
Range 120000-140000
completed (view)
Range 140000-160000
completed (view)
Range 160000-180000
completed (view)
Range 180000-200000
completed (view)
Range 200000-300000
completed (view)
Range 300000-400000
completed (view)
Range 400000-500000
completed (view)
Range 500000-600000
completed (view)
Range 600000-700000
completed (view)
Range 700000-800000
completed (view)
Range 800000-900000
completed (view)
Range 900000-1000000
completed (view)
Range 1000000-2000000
completed (view)
Range 2000000-3000000
completed (view)
Range 3000000-4000000
completed (view)
Range 4000000-5000000
completed (view)
Range 5000000-10000000
completed (view)
Range 10000000-15000000
completed (view)
Range 15000000-20000000
completed (view)
Range 20000000-25000000
completed (view)
Range 25000000-30000000
completed (view)
Range 30000000-35000000
completed (view)
Range 35000000-40000000
completed (view)
 
Not yet assigned Assigned,
not yet started
Assigned,
in progress
Entire interval
completed
Interval completed
class record found
40000000-10000
Lutz
40010000-20000
Lutz
40020000-30000
Lutz
40030000-40000
Lutz
40040000-50000
Lutz
40050000-60000
Lutz
40060000-70000
Lutz
40070000-80000
Lutz
40080000-90000
Lutz
40090000-00000
Lutz
40100000-10000
Lutz
40110000-20000
Lutz
40120000-30000
Lutz
40130000-40000
Lutz
40140000-50000
Lutz
40150000-60000
Lutz
40160000-70000
Lutz
40170000-80000
Lutz
40180000-90000
Lutz
40190000-00000
Lutz
40200000-10000
AntiRegex
40210000-20000
AntiRegex
40220000-30000
AntiRegex
40230000-40000
AntiRegex
40240000-50000
AntiRegex
40250000-60000
AntiRegex
40260000-70000
AntiRegex
40270000-80000
AntiRegex
40280000-90000
AntiRegex
40290000-00000
AntiRegex
40300000-10000
Federico
40310000-20000
Federico
40320000-30000
Federico
40330000-40000
Federico
40340000-50000
Federico
40350000-60000
Federico
40360000-70000
Federico
40370000-80000
Federico
40380000-90000
Federico
40390000-00000
Federico
40400000-10000
Luiz
40410000-20000
Luiz
40420000-30000
Luiz
40430000-40000
Luiz
40440000-50000
Luiz
40450000-60000
Luiz
40460000-70000
Luiz
40470000-80000
Luiz
40480000-90000
Luiz
40490000-00000
Luiz
40500000-10000
AntiRegex
40510000-20000
AntiRegex
40520000-30000
AntiRegex
40530000-40000
AntiRegex
40540000-50000
AntiRegex
40550000-60000
AntiRegex
40560000-70000
AntiRegex
40570000-80000
AntiRegex
40580000-90000
AntiRegex
40590000-00000
AntiRegex
40600000-10000
Wenjie
40610000-20000
Wenjie
40620000-30000
Wenjie
40630000-40000
Wenjie
40640000-50000
Wenjie
40650000-60000
Wenjie
40660000-70000
Wenjie
40670000-80000
Wenjie
40680000-90000
Wenjie
40690000-00000
Wenjie
40700000-10000
Wenjie
40710000-20000
Wenjie
40720000-30000
Wenjie
40730000-40000
Wenjie
40740000-50000
Wenjie
40750000-60000
Wenjie
40760000-70000
Wenjie
40770000-80000
Wenjie
40780000-90000
Wenjie
40790000-00000
Wenjie
40800000-10000
Wenjie
40810000-20000
Wenjie
40820000-30000
Wenjie
40830000-40000
Wenjie
40840000-50000
Wenjie
40850000-60000
Wenjie
40860000-70000
Wenjie
40870000-80000
Wenjie
40880000-90000
Wenjie
40890000-00000
Wenjie
40900000-10000
Wenjie
40910000-20000
Wenjie
40920000-30000
Wenjie
40930000-40000
Wenjie
40940000-50000
Wenjie
40950000-60000
Wenjie
40960000-70000
Wenjie
40970000-80000
Wenjie
40980000-90000
Wenjie
40990000-00000
Wenjie
41000000-10000
Kevin
41010000-20000
Kevin
41020000-30000
Kevin
41030000-40000
Kevin
41040000-50000
Kevin
41050000-60000
Kevin
41060000-70000
Kevin
41070000-80000
Kevin
41080000-90000
Kevin
41090000-00000
Kevin
41100000-10000
Kevin
41110000-20000
Kevin
41120000-30000
Kevin
41130000-40000
Kevin
41140000-50000
Kevin
41150000-60000
Kevin
41160000-70000
Kevin
41170000-80000
Kevin
41180000-90000
Kevin
41190000-00000
Kevin
41200000-10000
Kevin
41210000-20000
Kevin
41220000-30000
Kevin
41230000-40000
Kevin
41240000-50000
Kevin
41250000-60000
Kevin
41260000-70000
Kevin
41270000-80000
Kevin
41280000-90000
Kevin
41290000-00000
Kevin
41300000-10000
Kevin
41310000-20000
Kevin
41320000-30000
Kevin
41330000-40000
Kevin
41340000-50000
Kevin
41350000-60000
Kevin
41360000-70000
Kevin
41370000-80000
Kevin
41380000-90000
Kevin
41390000-00000
Kevin
41400000-10000
Kevin
41410000-20000
Kevin
41420000-30000
Kevin
41430000-40000
Kevin
41440000-50000
Kevin
41450000-60000
Kevin
41460000-70000
Kevin
41470000-80000
Kevin
41480000-90000
Kevin
41490000-00000
Kevin
41500000-10000
Kevin
41510000-20000
Kevin
41520000-30000
Kevin
41530000-40000
Kevin
41540000-50000
Kevin
41550000-60000
Kevin
41560000-70000
Kevin
41570000-80000
Kevin
41580000-90000
Kevin
41590000-00000
Kevin
41600000-10000
Kevin
41610000-20000
Kevin
41620000-30000
Kevin
41630000-40000
Kevin
41640000-50000
Kevin
41650000-60000
Kevin
41660000-70000
Kevin
41670000-80000
Kevin
41680000-90000
Kevin
41690000-00000
Kevin
41700000-10000
Kevin
41710000-20000
Kevin
41720000-30000
Kevin
41730000-40000
Kevin
41740000-50000
Kevin
41750000-60000
Kevin
41760000-70000
Kevin
41770000-80000
Kevin
41780000-90000
Kevin
41790000-00000
Kevin
41800000-10000
Kevin
41810000-20000
Kevin
41820000-30000
Kevin
41830000-40000
Kevin
41840000-50000
Kevin
41850000-60000
Kevin
41860000-70000
Kevin
41870000-80000
Kevin
41880000-90000
Kevin
41890000-00000
Kevin
41900000-10000
Kevin
41910000-20000
Kevin
41920000-30000
Kevin
41930000-40000
Kevin
41940000-50000
Kevin
41950000-60000
Kevin
41960000-70000
Kevin
41970000-80000
Kevin
41980000-90000
Kevin
41990000-00000
Kevin
42000000-10000
Luiz
42010000-20000
Luiz
42020000-30000
Luiz
42030000-40000
Luiz
42040000-50000
Luiz
42050000-60000
Luiz
42060000-70000
Luiz
42070000-80000
Luiz
42080000-90000
Luiz
42090000-00000
Luiz
42100000-10000
AntiRegex
42110000-20000
AntiRegex
42120000-30000
AntiRegex
42130000-40000
AntiRegex
42140000-50000
AntiRegex
42150000-60000
AntiRegex
42160000-70000
AntiRegex
42170000-80000
AntiRegex
42180000-90000
AntiRegex
42190000-00000
AntiRegex
42200000-10000
Wenjie
42210000-20000
Wenjie
42220000-30000
Wenjie
42230000-40000
Wenjie
42240000-50000
Wenjie
42250000-60000
Wenjie
42260000-70000
Wenjie
42270000-80000
Wenjie
42280000-90000
Wenjie
42290000-00000
Wenjie
42300000-10000
Wenjie
42310000-20000
Wenjie
42320000-30000
Wenjie
42330000-40000
Wenjie
42340000-50000
Wenjie
42350000-60000
Wenjie
42360000-70000
Wenjie
42370000-80000
Wenjie
42380000-90000
Wenjie
42390000-00000
Wenjie
42400000-10000
Wenjie
42410000-20000
Wenjie
42420000-30000
Wenjie
42430000-40000
Wenjie
42440000-50000
Wenjie
42450000-60000
Wenjie
42460000-70000
Wenjie
42470000-80000
Wenjie
42480000-90000
Wenjie
42490000-00000
Wenjie
42500000-10000
Wenjie
42510000-20000
Wenjie
42520000-30000
Wenjie
42530000-40000
Wenjie
42540000-50000
Wenjie
42550000-60000
Wenjie
42560000-70000
Wenjie
42570000-80000
Wenjie
42580000-90000
Wenjie
42590000-00000
Wenjie
42600000-10000
Lutz
42610000-20000
Lutz
42620000-30000
Lutz
42630000-40000
Lutz
42640000-50000
Lutz
42650000-60000
Lutz
42660000-70000
Lutz
42670000-80000
Lutz
42680000-90000
Lutz
42690000-00000
Lutz
42700000-10000
Lutz
42710000-20000
Lutz
42720000-30000
Lutz
42730000-40000
Lutz
42740000-50000
Lutz
42750000-60000
Lutz
42760000-70000
Lutz
42770000-80000
Lutz
42780000-90000
Lutz
42790000-00000
Lutz
42800000-10000
Luiz
42810000-20000
Luiz
42820000-30000
Luiz
42830000-40000
Luiz
42840000-50000
Luiz
42850000-60000
Luiz
42860000-70000
Luiz
42870000-80000
Luiz
42880000-90000
Luiz
42890000-00000
Luiz
42900000-10000
Daniel
42910000-20000
Daniel
42920000-30000
Daniel
42930000-40000
Daniel
42940000-50000
Daniel
42950000-60000
Daniel
42960000-70000
Daniel
42970000-80000
Daniel
42980000-90000
Daniel
42990000-00000
Daniel
43000000-10000
Kevin
43010000-20000
Kevin
43020000-30000
Kevin
43030000-40000
Kevin
43040000-50000
Kevin
43050000-60000
Kevin
43060000-70000
Kevin
43070000-80000
Kevin
43080000-90000
Kevin
43090000-00000
Kevin
43100000-10000
Kevin
43110000-20000
Kevin
43120000-30000
Kevin
43130000-40000
Kevin
43140000-50000
Kevin
43150000-60000
Kevin
43160000-70000
Kevin
43170000-80000
Kevin
43180000-90000
Kevin
43190000-00000
Kevin
43200000-10000
Kevin
43210000-20000
Kevin
43220000-30000
Kevin
43230000-40000
Kevin
43240000-50000
Kevin
43250000-60000
Kevin
43260000-70000
Kevin
43270000-80000
Kevin
43280000-90000
Kevin
43290000-00000
Kevin
43300000-10000
Kevin
43310000-20000
Kevin
43320000-30000
Kevin
43330000-40000
Kevin
43340000-50000
Kevin
43350000-60000
Kevin
43360000-70000
Kevin
43370000-80000
Kevin
43380000-90000
Kevin
43390000-00000
Kevin
43400000-10000
Kevin
43410000-20000
Kevin
43420000-30000
Kevin
43430000-40000
Kevin
43440000-50000
Kevin
43450000-60000
Kevin
43460000-70000
Kevin
43470000-80000
Kevin
43480000-90000
Kevin
43490000-00000
Kevin
43500000-10000
Kevin
43510000-20000
Kevin
43520000-30000
Kevin
43530000-40000
Kevin
43540000-50000
Kevin
43550000-60000
Kevin
43560000-70000
Kevin
43570000-80000
Kevin
43580000-90000
Kevin
43590000-00000
Kevin
43600000-10000
Kevin
43610000-20000
Kevin
43620000-30000
Kevin
43630000-40000
Kevin
43640000-50000
Kevin
43650000-60000
Kevin
43660000-70000
Kevin
43670000-80000
Kevin
43680000-90000
Kevin
43690000-00000
Kevin
43700000-10000
Kevin
43710000-20000
Kevin
43720000-30000
Kevin
43730000-40000
Kevin
43740000-50000
Kevin
43750000-60000
Kevin
43760000-70000
Kevin
43770000-80000
Kevin
43780000-90000
Kevin
43790000-00000
Kevin
43800000-10000
Kevin
43810000-20000
Kevin
43820000-30000
Kevin
43830000-40000
Kevin
43840000-50000
Kevin
43850000-60000
Kevin
43860000-70000
Kevin
43870000-80000
Kevin
43880000-90000
Kevin
43890000-00000
Kevin
43900000-10000
Kevin
43910000-20000
Kevin
43920000-30000
Kevin
43930000-40000
Kevin
43940000-50000
Kevin
43950000-60000
Kevin
43960000-70000
Kevin
43970000-80000
Kevin
43980000-90000
Kevin
43990000-00000
Kevin
44000000-10000
Eric
44010000-20000
Eric
44020000-30000
Eric
44030000-40000
Eric
44040000-50000
Eric
44050000-60000
Eric
44060000-70000
Eric
44070000-80000
Eric
44080000-90000
Eric
44090000-00000
Eric
44100000-10000
44110000-20000
44120000-30000
44130000-40000
44140000-50000
44150000-60000
44160000-70000
44170000-80000
44180000-90000
44190000-00000
44200000-10000
44210000-20000
44220000-30000
44230000-40000
44240000-50000
44250000-60000
44260000-70000
44270000-80000
44280000-90000
44290000-00000
44300000-10000
44310000-20000
44320000-30000
44330000-40000
44340000-50000
44350000-60000
44360000-70000
44370000-80000
44380000-90000
44390000-00000
44400000-10000
44410000-20000
44420000-30000
44430000-40000
44440000-50000
44450000-60000
44460000-70000
44470000-80000
44480000-90000
44490000-00000
44500000-10000
44510000-20000
44520000-30000
44530000-40000
44540000-50000
44550000-60000
44560000-70000
44570000-80000
44580000-90000
44590000-00000
44600000-10000
44610000-20000
44620000-30000
44630000-40000
44640000-50000
44650000-60000
44660000-70000
44670000-80000
44680000-90000
44690000-00000
44700000-10000
44710000-20000
44720000-30000
44730000-40000
44740000-50000
44750000-60000
44760000-70000
44770000-80000
44780000-90000
44790000-00000
44800000-10000
44810000-20000
44820000-30000
44830000-40000
44840000-50000
44850000-60000
44860000-70000
44870000-80000
44880000-90000
44890000-00000
44900000-10000
44910000-20000
44920000-30000
44930000-40000
44940000-50000
44950000-60000
44960000-70000
44970000-80000
44980000-90000
44990000-00000
Contributions by
EricEric Roosendaal, Netherlands (author) LutzLutz Nebe, Germany
KevinKevin Hebb, Alberta, Canada WenjieFang Wenjie, China
LuizLuiz Antonio Souza, Brazil DanielDaniel Podobinski
AntiRegexAntiRegex FedericoFederico Stella

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