Henri & Renaud Lifchitz's PRP Top records

What is a PRP ?

A PRP is a probable prime number, a number that nobody knows how to prove or disprove its primality.
Here are some criterions that can be used to recognize these numbers :

- N does not have any prime factor up to 2^32.
- N cannot be trivially written into a product.
- Take 3 square-free consecutive bases such that (b1/N)=(b2/N)=(b3/N)= -1. N should be such that b1^((N-1)/2)=b2^((N-1)/2)=b3^((N-1)/2)= -1 (mod N).
- Take a prime base such that (b/N)= -1 and b<>b1<>b2<>b3. N should pass the strong test in base b.
- or more (if someone has got an idea) !!!

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1-250	251-500	501-750	751-1000	1001-1250	1251-1500	1501-1750	1751-2000
2001-2250	2251-2500	2501-2750	2751-3000	3001-3250	3251-3500	3501-3750	3751-4000
4001-4250	4251-4500	4501-4750	4751-5000	5001-5250	5251-5500	5501-5750	5751-6000
6001-6250	6251-6500	6501-6750	6751-7000	7001-7250	7251-7500	7501-7750	7751-8000
8001-8250	8251-8500	8501-8750	8751-9000	9001-9250	9251-9500	9501-9750	9751-10000

Rank	Probable prime	Digits (> 50000)	Who ?	When ?
1751	2^842325+25907	253566	Enzo Doria	11/2023
1752	2^842209+1876037	253531	Enzo Doria	07/2016
1753	2^842123-59197	253505	Enzo Doria	10/2015
1754	(8*10^253313-53)/9	253313	Serge Batalov	11/2022
1755	(28*10^253210+191)/3	253211	Robert Price	07/2023
1756	2^840797-3	253106	Paul Bourdelais	06/2019
1757	2^840716-2969	253081	Yves Minet	05/2016
1758	2^840358-462491	252973	Enzo Doria	08/2015
1759	2^840310+1878379	252959	Enzo Doria	08/2016
1760	2^840203-21	252927	Stefano Morozzi	07/2022
1761	11^242579-60	252620	Enzo Doria	10/2012
1762	45^152659+2	252378	Robert Price	09/2015
1763	(95^127583+1)/96	252322	Paul Bourdelais	07/2019
1764	7*10^252209-17	252210	Robert Price	12/2022
1765	2^837725+1869377	252181	Enzo Doria	05/2016
1766	2^837536-311039	252124	Enzo Doria	06/2015
1767	21^190632-2	252058	Robert Price	07/2015
1768	2^837242+1873297	252035	Enzo Doria	06/2016
1769	2^836995+226575	251961	Enzo Doria	10/2024
1770	2^836656-2787929	251859	Enzo Doria	11/2015
1771	2^836548+219061	251827	Enzo Doria	02/2024
1772	2^836380+1875541	251776	Enzo Doria	07/2016
1773	(359^98327-1)/358	251233	Alexander Zhirkov	11/2017
1774	tau(41^28288)	250924	Nik Lygeros / Olivier Rozier	10/2013
1775	(28*10^250655+113)/3	250656	Robert Price	06/2023
1776	2^832511-461197	250611	Enzo Doria	07/2015
1777	2^832505+1881137	250609	Enzo Doria	11/2016
1778	2^832363+583295	250567	Enzo Doria	12/2016
1779	2^832244-403635	250531	Enzo Doria	01/2014
1780	(14*10^250336-41)/9	250337	Serge Batalov	01/2023
1781	2^831528+24811	250315	Enzo Doria	11/2023
1782	2^831157+1880657	250204	Enzo Doria	11/2016
1783	2^831088-7200899	250183	Enzo Doria	01/2015
1784	2^830956-1349	250143	Yves Minet	07/2015
1785	2^830699+220583	250066	Enzo Doria	03/2024
1786	2^830037+282317	249867	Enzo Doria	09/2016
1787	2^829589-113653	249732	Enzo Doria	09/2014
1788	(4*10^249550-7)/3	249551	Serge Batalov	01/2023
1789	(103*10^249399+17)/3	249401	Robert Price	04/2023
1790	2^828281-3193	249338	Yves Minet	08/2016
1791	(2^828140-19)/3	249295	Stefano Morozzi	08/2022
1792	2^828064-2785619	249273	Enzo Doria	10/2015
1793	2^827602+60409	249134	Enzo Doria	03/2016
1794	2^827306+212419	249044	Enzo Doria	09/2023
1795	10^249010+348861	249011	Patrick De Geest	04/2016
1796	10^249010-21	249010	Serge Batalov	12/2014
1797	2^826733+1882907	248872	Enzo Doria	12/2016
1798	2^825800+22441	248591	Enzo Doria	10/2023
1799	2^825682+1876549	248556	Enzo Doria	07/2016
1800	2^824991-114121	248348	Enzo Doria	12/2014
1801	2^824642-362727	248242	Enzo Doria	12/2013
1802	2^824565-114265	248219	Enzo Doria	01/2015
1803	2^824325-25	248147	Boyan Hu	12/2024
1804	(73*10^248145-1)/9	248146	Robert Price	01/2015
1805	2^823321+219407	247845	Enzo Doria	02/2024
1806	(2^823337+1)/(3*362268281)	247841	Gord Palameta	08/2018
1807	(13*10^247793-43)/3	247794	Robert Price	08/2023
1808	(2^822971-1)/6583769/28211445881/21255852651726486149207	247700	Robert Kinser	09/2016
1809	2^822296+76501	247536	Enzo Doria	05/2016
1810	2^821590-114167	247324	Enzo Doria	12/2014
1811	2^821512-2790659	247300	Enzo Doria	12/2015
1812	(21996^57121-1)/(21996^239-1)	247002	Ryan Propper	11/2023
1813	2^820356+7	246952	Jon Grantham	08/2023
1814	2^820077+382847	246868	Enzo Doria	11/2016
1815	2^820008+81	246848	Henri Lifchitz	01/2025
1816	2^820001+81269	246845	Enzo Doria	07/2016
1817	2^819463-59197	246683	Enzo Doria	10/2015
1818	2^819296+80581	246633	Enzo Doria	07/2016
1819	2^818764+21573	246473	Enzo Doria	11/2023
1820	2^817852+215491	246198	Enzo Doria	11/2023
1821	2^817160-350369	245990	Enzo Doria	06/2015
1822	2^816039-19	245653	Stefano Morozzi	07/2022
1823	2^816029+219407	245650	Enzo Doria	02/2024
1824	(71*10^245558-17)/9	245559	Serge Batalov	01/2023
1825	5*3^514648+2^514648	245551	Jon Grantham	08/2023
1826	88093#+(653879#)/(88093#)	245374	Makoto Morimoto	11/2017
1827	2^815111-113857	245373	Enzo Doria	10/2014
1828	(34555^54289-1)/(34555^233-1)	245334	Ryan Propper	11/2023
1829	2^814914-4001	245314	Yves Minet	05/2017
1830	846^83761-845^83761	245200	Jean-Louis Charton	12/2012
1831	2^814356-2790449	245146	Enzo Doria	12/2015
1832	2^814276-459029	245122	Enzo Doria	04/2015
1833	2^814023+180923	245046	Enzo Doria	07/2016
1834	2^813496+216751	244887	Enzo Doria	12/2023
1835	(3^513059-2^513059)/(1026119*5430216457)	244776	Mike Oakes	03/2017
1836	3^513007+16	244767	Robert Price	04/2020
1837	(46^147197-31^147197)/15	244752	Aurel Gibier	06/2024
1838	2^811882+27289	244401	Enzo Doria	12/2023
1839	2^811842-113675	244389	Enzo Doria	09/2014
1840	2^811132-2787929	244176	Enzo Doria	11/2015
1841	2^809746-2790971	243758	Enzo Doria	01/2016
1842	(14*10^243724-197)/3	243725	Robert Price	03/2023
1843	2^808767-3295	243464	Yves Minet	12/2016
1844	2^808621-113809	243420	Enzo Doria	09/2014
1845	2^808199+29693	243293	Enzo Doria	03/2024
1846	2^807724+1879621	243150	Enzo Doria	09/2016
1847	2^807417+217787	243057	Enzo Doria	01/2024
1848	(23*10^242909+91)/3	242910	Robert Price	03/2023
1849	2^806708+20371	242844	Enzo Doria	08/2023
1850	2*10^242822-91	242823	Robert Price	02/2023
1851	20^186554-3	242713	Paul Bourdelais	12/2020
1852	2^805843-113611	242583	Enzo Doria	08/2014
1853	2^805745-459763	242554	Enzo Doria	05/2015
1854	2^805353+782687	242436	Enzo Doria	11/2016
1855	(19*10^242362-7)/3	242363	Robert Price	12/2023
1856	2^804895+29963	242298	Enzo Doria	03/2024
1857	2^804725+28229	242247	Enzo Doria	01/2024
1858	6^311257+5	242206	Paul Bourdelais	02/2021
1859	(21^242194)%(10^242194)	242194	Henri Lifchitz	06/2025
1860	2^804277-417933	242112	Enzo Doria	01/2014
1861	2^803468-269039	241868	Enzo Doria	10/2013
1862	2^803172+80851	241779	Enzo Doria	07/2016
1863	2^803011+220073	241731	Enzo Doria	03/2024
1864	3^506233-2	241535	Robert Price	11/2013
1865	2^802025-25999	241434	Enzo Doria	10/2013
1866	(3^505823+3^252912+1)/7	241339	Serge Batalov	03/2014
1867	2^801575+25073	241299	Enzo Doria	11/2023
1868	2^801303+1872923	241217	Enzo Doria	05/2016
1869	2^801105+216977	241157	Enzo Doria	12/2023
1870	(23*10^241048-143)/3	241049	Robert Price	12/2023
1871	2^800579-1862947	240999	Enzo Doria	12/2015
1872	2^799999+16205	240824	Norman Luhn	09/2023
1873	3^504206+2	240568	Luke W. Richards	03/2018
1874	2^798973-26283	240515	Enzo Doria	10/2013
1875	2^798671-69487	240424	Enzo Doria	12/2015
1876	2^797220+79831	239988	Enzo Doria	06/2016
1877	2^796910-26001	239894	Enzo Doria	10/2013
1878	(97^120721-1)/811245216	239837	Paul Vanderveen	06/2025
1879	2^796598+653119	239800	Enzo Doria	12/2016
1880	2^796432-1859729	239750	Enzo Doria	11/2015
1881	2^796002-1852211	239621	Enzo Doria	08/2015
1882	2^795884+214081	239585	Enzo Doria	10/2023
1883	2^795709+75767	239533	Enzo Doria	04/2016
1884	2^795708+81721	239532	Enzo Doria	08/2016
1885	2^795468-2786249	239460	Enzo Doria	10/2015
1886	2^795442+80779	239452	Enzo Doria	07/2016
1887	2^795075-1852057	239342	Enzo Doria	08/2015
1888	(86^123677+1)/87	239252	Paul Bourdelais	01/2019
1889	2^794043+1875023	239031	Enzo Doria	06/2016
1890	2^793347-69577	238822	Enzo Doria	01/2016
1891	5*2^793288+3	238805	Jon Grantham	07/2023
1892	2^792988-344429	238714	Enzo Doria	08/2015
1893	2^792700-2786369	238627	Enzo Doria	11/2015
1894	2^792663-1844797	238616	Enzo Doria	06/2015
1895	2^792605-291943	238598	Enzo Doria	07/2015
1896	2^792366+218599	238526	Enzo Doria	01/2024
1897	(2^792061-2^396031+1)/5	238434	Thomas Ritschel	03/2014
1898	2^791321+30077	238212	Enzo Doria	03/2024
1899	4*10^238163+21	238164	Robert Price	12/2022
1900	(26*10^238157-77)/3	238158	Robert Price	03/2023
1901	10^237670+9	237671	Robert Price	08/2023
1902	2^789373+1869377	237625	Enzo Doria	05/2016
1903	((10^59387+1)^3(10^59387+1+10^29694)-(10^118774+10^59387)(10^29694-1)+10^178161)/27961	237544	Serge Batalov	04/2015
1904	Phi(1187740M,10)	237544	Anonymous	03/2025
1905	2^789033+218537	237523	Enzo Doria	01/2024
1906	2^788942+1866409	237496	Enzo Doria	02/2016
1907	2^788844-114329	237466	Enzo Doria	01/2015
1908	2^788705-1859713	237424	Enzo Doria	11/2015
1909	2^788325+224789	237310	Enzo Doria	07/2024
1910	15^201475+14	236953	Alfred Reich	10/2023
1911	2^786663+219173	236810	Enzo Doria	02/2024
1912	2^786180+1871971	236664	Enzo Doria	05/2016
1913	11^227092-90	236492	Enzo Doria	11/2012
1914	2^785260+1866361	236387	Enzo Doria	02/2016
1915	2^785220+1880611	236375	Enzo Doria	10/2016
1916	(2^784689-15)/7	236215	Stefano Morozzi	08/2022
1917	19^184650-2	236122	Robert Price	10/2014
1918	10^236059+216513	236060	Patrick De Geest	04/2016
1919	10^236059-20909	236059	Robert Price	09/2015
1920	2^783988+38011	236004	Enzo Doria	10/2024
1921	2^783893-21	235976	Stefano Morozzi	07/2022
1922	(47^140983-1)/2792206142311142462	235719	Paul Vanderveen	06/2025
1923	2^782821+37577	235653	Enzo Doria	10/2024
1924	(87^121487-1)/86	235625	Paul Bourdelais	12/2018
1925	2^782634-113981	235597	Enzo Doria	11/2014
1926	2^782423+1879733	235533	Enzo Doria	09/2016
1927	(10^(2117707+1)+1210^117707-1)/3	235415	Robert Price	10/2023
1928	(2^781970)/(781970^2)	235385	Henri Lifchitz	06/2025
1929	2^781682-2789543	235310	Enzo Doria	12/2015
1930	2^780481+21489	234949	Enzo Doria	05/2024
1931	2^780408-113453	234927	Enzo Doria	08/2014
1932	7*10^234915+9	234916	Robert Price	04/2023
1933	2^780368-1864829	234915	Enzo Doria	01/2016
1934	2^780284+7	234889	Jon Grantham	08/2023
1935	2^779593-1836559	234681	Enzo Doria	05/2015
1936	(8713#+(549391#)/(8713#))/360295171	234487	Makoto Morimoto	11/2017
1937	(5^335429+1)/6	234455	Paul Bourdelais	08/2010
1938	2^778788+22201	234439	Enzo Doria	09/2023
1939	2^778395-113617	234321	Enzo Doria	08/2014
1940	5*2^778090+3	234230	Jon Grantham	07/2023
1941	(21430^54289-1)/(21430^233-1)	234118	Ryan Propper	11/2023
1942	(5*10^234054-101)/3	234055	Robert Price	08/2023
1943	23*10^234025-7	234027	Robert Price	10/2022
1944	2^777170+21489	233952	Enzo Doria	05/2024
1945	Phi(78125,5517)	233857	Anonymous	09/2022
1946	5^334359-3^334359-1	233707	Jon Grantham	08/2023
1947	2^776245-2792353	233674	Enzo Doria	02/2016
1948	49748^49748+49735^49735	233656	Henri Lifchitz	11/2024
1949	2^776060-114029	233618	Enzo Doria	11/2014
1950	2^775987-2789557	233596	Enzo Doria	12/2015
1951	2*10^233564-91	233565	Robert Price	02/2023
1952	2^775865+21489	233559	Enzo Doria	05/2024
1953	2^775672+1866721	233501	Enzo Doria	03/2016
1954	2^775238+57	233370	Stefano Morozzi	05/2021
1955	(11^223999+1)/12	233270	Paul Bourdelais	02/2010
1956	U(1302049)	233238	Serge Batalov	07/2024
1957	2^774118+1885789	233033	Enzo Doria	04/2017
1958	21^176191-20^176191	232964	Jean-Louis Charton	01/2015
1959	2^773723+217523	232914	Enzo Doria	01/2024
1960	2^773679-113425	232901	Enzo Doria	08/2014
1961	(7*10^232620+23)/3	232621	Robert Price	05/2023
1962	10^232599+192489	232600	Patrick De Geest	12/2013
1963	10^232599-3	232599	Markus Tervooren	10/2010
1964	2^772552-458879	232562	Enzo Doria	04/2015
1965	2^772214+1874899	232460	Enzo Doria	06/2016
1966	2^771994-1862771	232394	Enzo Doria	12/2015
1967	2^771889+1876037	232362	Enzo Doria	07/2016
1968	2^771660+1866511	232293	Enzo Doria	02/2016
1969	5^332150-18188	232163	Enzo Doria	06/2014
1970	2^771227+61121	232163	Boyan Hu	05/2024
1971	2^770623+212543	231981	Enzo Doria	09/2023
1972	3^485977-2^485977	231870	Mike Oakes	09/2009
1973	2^770082-114161	231818	Enzo Doria	01/2015
1974	2^769791+25523	231731	Enzo Doria	11/2023
1975	7^274120-2	231659	Paul Bourdelais	08/2023
1976	(20^177967+1)/21	231540	Paul Bourdelais	05/2013
1977	2^769011+81	231496	Henri Lifchitz	01/2025
1978	(71^125029-1)/105024430	231453	Paul Vanderveen	06/2025
1979	(4*10^231254+23)/9	231254	Serge Batalov	11/2022
1980	2^768205+22217	231253	Enzo Doria	09/2023
1981	49262^49262-49247^49247	231163	Henri Lifchitz	11/2024
1982	2^767622-9221	231078	Lelio R Paula	01/2016
1983	2^767344+1880311	230994	Enzo Doria	09/2016
1984	8*10^230921-13	230922	Robert Price	08/2023
1985	(3^483611-1)/2	230741	Paul Bourdelais	02/2010
1986	(10^230706+179)/9	230706	Serge Batalov	12/2014
1987	2^766309+1875257	230682	Enzo Doria	06/2016
1988	(26131^52441-1)/(26131^229-1)	230629	Ryan Propper	11/2023
1989	2^765635+1879883	230480	Enzo Doria	09/2016
1990	43^141090+141090	230467	Kellen Shenton	06/2023
1991	(26*10^230394-119)/3	230395	Robert Price	07/2023
1992	2^764348-113697	230092	Enzo Doria	09/2014
1993	2^764131+78863	230027	Enzo Doria	05/2016
1994	2^763701+60197	229897	Enzo Doria	03/2016
1995	4*10^229836+21	229837	Robert Price	12/2022
1996	2^763362+27799	229795	Enzo Doria	01/2024
1997	2^762841-25905	229639	Enzo Doria	10/2013
1998	2^762659+212633	229584	Enzo Doria	09/2023
1999	77*10^229211+3	229213	Robert Price	11/2023
2000	2^761117-113569	229120	Enzo Doria	08/2014

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Probable Primes Top 10000

(301901 PRPs in the top)