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	2^874566+30049	263271	Enzo Doria	03/2024
1752	3^551491+16	263129	Robert Price	04/2020
1753	2^874073+2792957	263123	Enzo Doria	02/2016
1754	(7*10^263006-19)/3	263007	Robert Price	10/2023
1755	2^873628+1878751	262989	Enzo Doria	08/2016
1756	2^873497+20837	262949	Enzo Doria	08/2023
1757	2^873288-269	262886	Yves Minet	01/2015
1758	(2*10^262874+7)/9	262874	Rytis Slatkevicius	01/2023
1759	(28*10^262655-43)/3	262656	Robert Price	04/2023
1760	(2*10^262603-11)/9	262603	Serge Batalov	11/2022
1761	2^871991-4207	262496	Yves Minet	03/2021
1762	(23*10^262324+7)/3	262325	Robert Price	05/2023
1763	2^871146-3173	262242	Yves Minet	07/2016
1764	(10^(2131020+1)+6310^131020-1)/9	262041	Robert Price	08/2024
1765	2^869601-163	261776	Yves Minet	01/2015
1766	(2*10^261704+61)/9	261704	Serge Batalov	11/2022
1767	2^869326+282859	261694	Enzo Doria	11/2016
1768	2^869035-114181	261606	Enzo Doria	12/2014
1769	2^868817+26777	261540	Enzo Doria	12/2023
1770	3^547850+9000004	261391	Enzo Doria	10/2023
1771	Phi(156793,2^7)	261261	Henri Lifchitz	10/2025
1772	4*10^261248+91	261249	Robert Price	11/2022
1773	55083^55083+1282^1282	261150	Henri Lifchitz	10/2024
1774	2^866908+34891	260966	Enzo Doria	07/2024
1775	2^865715+80303	260607	Enzo Doria	07/2016
1776	2^865474+23209	260534	Enzo Doria	10/2023
1777	2^865238+214759	260463	Enzo Doria	11/2023
1778	2^865048+1882411	260406	Enzo Doria	12/2016
1779	2^864899-113871	260361	Enzo Doria	10/2014
1780	(16*10^260256-91)/3	260257	Robert Price	11/2022
1781	(7*10^260198-61)/9	260198	Erik Branger	11/2011
1782	2^864298-2788421	260180	Enzo Doria	12/2015
1783	2^864039-2791357	260102	Enzo Doria	01/2016
1784	2^863621-113833	259976	Enzo Doria	10/2014
1785	10^259945-11	259945	Mischa Rodermond	04/2023
1786	2^863433+34877	259920	Enzo Doria	07/2024
1787	(28*10^259897+113)/3	259898	Robert Price	06/2023
1788	2^862837+75767	259740	Enzo Doria	05/2016
1789	2^862637-31	259680	Jorge Menendez	05/2019
1790	2^862088+1874941	259515	Enzo Doria	06/2016
1791	2^861987-134557	259484	Hans Havermann	10/2018
1792	(14*10^259431-143)/3	259432	Robert Price	05/2023
1793	2^861516-1854029	259343	Enzo Doria	09/2015
1794	2^860975-1853977	259180	Enzo Doria	09/2015
1795	3^543128+16	259138	Robert Price	04/2020
1796	2^860625-1858843	259074	Enzo Doria	10/2015
1797	2^860110+77689	258919	Enzo Doria	05/2016
1798	2^859600+1880371	258766	Enzo Doria	10/2016
1799	2^859433+494711	258716	Makoto Morimoto	10/2013
1801	(2^859433-44)/(2^2*3)	258715	Makoto Morimoto	08/2019
1800	(2^859431-11)/3	258715	Stefano Morozzi	08/2022
1802	(13*10^258710-43)/3	258711	Robert Price	08/2023
1803	(2^859433+39899)/(73390746301)	258705	Makoto Morimoto	10/2016
1804	2^859240+1875271	258658	Enzo Doria	06/2016
1805	Tau(971^15738)	258571	Nik Lygeros / Olivier Rozier	05/2015
1806	2^858812+30421	258529	Enzo Doria	03/2024
1807	(23*10^258494-47)/3	258495	Robert Price	09/2023
1808	(144^119671+1)/145	258292	Paul Bourdelais	08/2019
1809	2^857608+105	258166	Stefano Morozzi	05/2021
1810	(11*2^857159-13)/15	258031	Renaud Lifchitz	08/2011
1811	2^857016-633113	257988	Enzo Doria	12/2013
1812	2^855732-113969	257602	Enzo Doria	10/2014
1813	(5*10^257431+91)/3	257432	Robert Price	08/2023
1814	2^853682-3911	256984	Enzo Doria	05/2014
1815	11^246668-90	256879	Enzo Doria	12/2012
1816	2^853181+30287	256834	Enzo Doria	03/2024
1817	5*2^852698+3	256689	Jon Grantham	07/2023
1818	(23*10^256654+7)/3	256655	Robert Price	05/2023
1819	2^851904-113939	256449	Enzo Doria	10/2014
1820	2^851725-851725^2	256395	Henri Lifchitz	03/2019
1821	11^246167-90	256357	Enzo Doria	12/2012
1822	(85*10^256301-1)/3	256303	Robert Price	12/2022
1823	(10^256187+7)/63443/148782853	256175	Alfred Reich	10/2021
1824	2^850700-569049	256087	Enzo Doria	11/2013
1825	2^850675+153	256079	Stefano Morozzi	05/2021
1826	21^193601-20^193601	255983	Jean-Louis Charton	02/2015
1827	(37^163193+1)/38	255918	Paul Bourdelais	07/2019
1828	(14*10^255805-83)/3	255806	Robert Price	11/2022
1829	2^849316+25861	255670	Enzo Doria	12/2023
1830	2^849177-114025	255628	Enzo Doria	12/2014
1831	2*10^255442-21	255443	Robert Price	08/2023
1832	2^848502-3173	255425	Yves Minet	07/2016
1833	2^848178-140291	255328	Enzo Doria	01/2014
1834	7*10^255167+87	255168	Robert Price	11/2022
1835	2^847622-2441	255160	Yves Minet	02/2016
1836	2^847291+182843	255061	Enzo Doria	11/2016
1837	2^847174+1879429	255025	Enzo Doria	09/2016
1838	2^846881+215837	254937	Enzo Doria	12/2023
1839	Phi(475779,2^3)	254889	Henri Lifchitz	12/2025
1840	24*29^174239+13361	254809	Curtis Bright	04/2015
1841	22*10^254639+7	254641	Robert Price	10/2022
1842	2^845633-933075	254561	Paul Bourdelais	11/2021
1843	2^845610-1868591	254554	Enzo Doria	04/2016
1844	2^845484+81931	254517	Enzo Doria	08/2016
1845	2^845402-114761	254492	Enzo Doria	05/2015
1846	Phi(115655,561)	254335	Henri Lifchitz	12/2025
1847	98*10^254173-9	254175	Robert Price	05/2023
1848	2^844334-2792441	254170	Enzo Doria	02/2016
1849	2*10^254162+69	254163	Robert Price	08/2023
1850	(4*10^254107+11)/3	254108	Tyler Busby	02/2023
1851	11^243796-90	253888	Enzo Doria	12/2012
1852	(10^253891+7)/44777/79843/16940711	253875	Alfred Reich	10/2021
1853	30^171733-29^171733	253671	Jean-Louis Charton	10/2018
1854	2^842325+25907	253566	Enzo Doria	11/2023
1855	2^842209+1876037	253531	Enzo Doria	07/2016
1856	2^842123-59197	253505	Enzo Doria	10/2015
1857	(8*10^253313-53)/9	253313	Serge Batalov	11/2022
1858	(28*10^253210+191)/3	253211	Robert Price	07/2023
1859	2^840797-3	253106	Paul Bourdelais	06/2019
1860	2^840716-2969	253081	Yves Minet	05/2016
1861	2^840358-462491	252973	Enzo Doria	08/2015
1862	2^840310+1878379	252959	Enzo Doria	08/2016
1863	2^840203-21	252927	Stefano Morozzi	07/2022
1864	11^242579-60	252620	Enzo Doria	10/2012
1865	45^152659+2	252378	Robert Price	09/2015
1866	(95^127583+1)/96	252322	Paul Bourdelais	07/2019
1867	7*10^252209-17	252210	Robert Price	12/2022
1868	2^837725+1869377	252181	Enzo Doria	05/2016
1869	2^837536-311039	252124	Enzo Doria	06/2015
1870	21^190632-2	252058	Robert Price	07/2015
1871	2^837242+1873297	252035	Enzo Doria	06/2016
1872	2^836995+226575	251961	Enzo Doria	10/2024
1873	2^836656-2787929	251859	Enzo Doria	11/2015
1874	2^836548+219061	251827	Enzo Doria	02/2024
1875	2^836380+1875541	251776	Enzo Doria	07/2016
1876	(359^98327-1)/358	251233	Alexander Zhirkov	11/2017
1877	tau(41^28288)	250924	Nik Lygeros / Olivier Rozier	10/2013
1878	Phi(137951,-100)	250801	Henri Lifchitz	12/2025
1879	Phi(74531,11#)	250691	Henri Lifchitz	12/2025
1880	(28*10^250655+113)/3	250656	Robert Price	06/2023
1881	2^832511-461197	250611	Enzo Doria	07/2015
1882	2^832505+1881137	250609	Enzo Doria	11/2016
1883	2^832363+583295	250567	Enzo Doria	12/2016
1884	2^832244-403635	250531	Enzo Doria	01/2014
1885	(14*10^250336-41)/9	250337	Serge Batalov	01/2023
1886	2^831528+24811	250315	Enzo Doria	11/2023
1887	2^831157+1880657	250204	Enzo Doria	11/2016
1888	2^831088-7200899	250183	Enzo Doria	01/2015
1889	2^830956-1349	250143	Yves Minet	07/2015
1890	2^830699+220583	250066	Enzo Doria	03/2024
1891	2^830037+282317	249867	Enzo Doria	09/2016
1892	2^829589-113653	249732	Enzo Doria	09/2014
1893	(4*10^249550-7)/3	249551	Serge Batalov	01/2023
1894	(103*10^249399+17)/3	249401	Robert Price	04/2023
1895	2^828281-3193	249338	Yves Minet	08/2016
1896	(2^828140-19)/3	249295	Stefano Morozzi	08/2022
1897	2^828064-2785619	249273	Enzo Doria	10/2015
1898	2^827602+60409	249134	Enzo Doria	03/2016
1899	2^827306+212419	249044	Enzo Doria	09/2023
1900	10^249010+348861	249011	Patrick De Geest	04/2016
1901	10^249010-21	249010	Serge Batalov	12/2014
1902	2^826733+1882907	248872	Enzo Doria	12/2016
1903	2^825800+22441	248591	Enzo Doria	10/2023
1904	2^825682+1876549	248556	Enzo Doria	07/2016
1905	2^824991-114121	248348	Enzo Doria	12/2014
1906	2^824642-362727	248242	Enzo Doria	12/2013
1907	2^824565-114265	248219	Enzo Doria	01/2015
1908	2^824325-25	248147	Boyan Hu	12/2024
1909	(73*10^248145-1)/9	248146	Robert Price	01/2015
1910	2^823321+219407	247845	Enzo Doria	02/2024
1911	(2^823337+1)/(3*362268281)	247841	Gord Palameta	08/2018
1912	(13*10^247793-43)/3	247794	Robert Price	08/2023
1913	(2^822971-1)/6583769/28211445881/21255852651726486149207	247700	Robert Kinser	09/2016
1914	2^822296+76501	247536	Enzo Doria	05/2016
1915	2^821590-114167	247324	Enzo Doria	12/2014
1916	2^821512-2790659	247300	Enzo Doria	12/2015
1917	(21996^57121-1)/(21996^239-1)	247002	Ryan Propper	11/2023
1918	2^820356+7	246952	Jon Grantham	08/2023
1919	2^820077+382847	246868	Enzo Doria	11/2016
1920	2^820008+81	246848	Henri Lifchitz	01/2025
1921	2^820001+81269	246845	Enzo Doria	07/2016
1922	2^819463-59197	246683	Enzo Doria	10/2015
1923	2^819296+80581	246633	Enzo Doria	07/2016
1924	2^818764+21573	246473	Enzo Doria	11/2023
1925	2^817852+215491	246198	Enzo Doria	11/2023
1926	2^817160-350369	245990	Enzo Doria	06/2015
1927	2^816039-19	245653	Stefano Morozzi	07/2022
1928	2^816029+219407	245650	Enzo Doria	02/2024
1929	(71*10^245558-17)/9	245559	Serge Batalov	01/2023
1930	5*3^514648+2^514648	245551	Jon Grantham	08/2023
1931	88093#+(653879#)/(88093#)	245374	Makoto Morimoto	11/2017
1932	2^815111-113857	245373	Enzo Doria	10/2014
1933	(34555^54289-1)/(34555^233-1)	245334	Ryan Propper	11/2023
1934	2^814914-4001	245314	Yves Minet	05/2017
1935	846^83761-845^83761	245200	Jean-Louis Charton	12/2012
1936	2^814356-2790449	245146	Enzo Doria	12/2015
1937	2^814276-459029	245122	Enzo Doria	04/2015
1938	2^814023+180923	245046	Enzo Doria	07/2016
1939	2^813496+216751	244887	Enzo Doria	12/2023
1940	(3^513059-2^513059)/(1026119*5430216457)	244776	Mike Oakes	03/2017
1941	3^513007+16	244767	Robert Price	04/2020
1942	(46^147197-31^147197)/15	244752	Aurel Gibier	06/2024
1943	(2543*17^198855-15)/16	244684	Eric Chen	01/2026
1944	2^811882+27289	244401	Enzo Doria	12/2023
1945	2^811842-113675	244389	Enzo Doria	09/2014
1946	2^811132-2787929	244176	Enzo Doria	11/2015
1947	2^809746-2790971	243758	Enzo Doria	01/2016
1948	(14*10^243724-197)/3	243725	Robert Price	03/2023
1949	2^808767-3295	243464	Yves Minet	12/2016
1950	2^808621-113809	243420	Enzo Doria	09/2014
1951	2^808199+29693	243293	Enzo Doria	03/2024
1952	2^807724+1879621	243150	Enzo Doria	09/2016
1953	2^807417+217787	243057	Enzo Doria	01/2024
1954	(23*10^242909+91)/3	242910	Robert Price	03/2023
1955	2^806708+20371	242844	Enzo Doria	08/2023
1956	2*10^242822-91	242823	Robert Price	02/2023
1957	20^186554-3	242713	Paul Bourdelais	12/2020
1958	2^805843-113611	242583	Enzo Doria	08/2014
1959	2^805745-459763	242554	Enzo Doria	05/2015
1960	2^805353+782687	242436	Enzo Doria	11/2016
1961	(19*10^242362-7)/3	242363	Robert Price	12/2023
1962	2^804895+29963	242298	Enzo Doria	03/2024
1963	2^804725+28229	242247	Enzo Doria	01/2024
1964	6^311257+5	242206	Paul Bourdelais	02/2021
1965	(21^242194)%(10^242194)	242194	Henri Lifchitz	06/2025
1966	2^804277-417933	242112	Enzo Doria	01/2014
1967	2^803468-269039	241868	Enzo Doria	10/2013
1968	2^803172+80851	241779	Enzo Doria	07/2016
1969	2^803011+220073	241731	Enzo Doria	03/2024
1970	3^506233-2	241535	Robert Price	11/2013
1971	2^802025-25999	241434	Enzo Doria	10/2013
1972	(3^505823+3^252912+1)/7	241339	Serge Batalov	03/2014
1973	2^801575+25073	241299	Enzo Doria	11/2023
1974	2^801303+1872923	241217	Enzo Doria	05/2016
1975	2^801105+216977	241157	Enzo Doria	12/2023
1976	(23*10^241048-143)/3	241049	Robert Price	12/2023
1977	2^800579-1862947	240999	Enzo Doria	12/2015
1978	2^799999+16205	240824	Norman Luhn	09/2023
1979	3^504206+2	240568	Luke W. Richards	03/2018
1980	2^798973-26283	240515	Enzo Doria	10/2013
1981	Phi(114205,3^7)	240470	Henri Lifchitz	12/2025
1982	2^798671-69487	240424	Enzo Doria	12/2015
1983	2^797220+79831	239988	Enzo Doria	06/2016
1984	2^796910-26001	239894	Enzo Doria	10/2013
1985	(97^120721-1)/811245216	239837	Paul Vanderveen	06/2025
1986	2^796598+653119	239800	Enzo Doria	12/2016
1987	2^796432-1859729	239750	Enzo Doria	11/2015
1988	2^796002-1852211	239621	Enzo Doria	08/2015
1989	2^795884+214081	239585	Enzo Doria	10/2023
1990	2^795709+75767	239533	Enzo Doria	04/2016
1991	2^795708+81721	239532	Enzo Doria	08/2016
1992	2^795468-2786249	239460	Enzo Doria	10/2015
1993	2^795442+80779	239452	Enzo Doria	07/2016
1994	2^795075-1852057	239342	Enzo Doria	08/2015
1995	(86^123677+1)/87	239252	Paul Bourdelais	01/2019
1996	2^794043+1875023	239031	Enzo Doria	06/2016
1997	2^793347-69577	238822	Enzo Doria	01/2016
1998	5*2^793288+3	238805	Jon Grantham	07/2023
1999	2^792988-344429	238714	Enzo Doria	08/2015
2000	2^792700-2786369	238627	Enzo Doria	11/2015

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