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	10^282493+632551	282494	Patrick De Geest	02/2017
1753	10^282493-9^282493	282493	Jean-Louis Charton	03/2007
1752	10^282493-132327	282493	Patrick De Geest	02/2017
1754	3^591827-2^591827	282374	Mike Oakes	08/2009
1755	Tau(509^18946)	282048	Nik Lygeros / Olivier Rozier	05/2015
1756	Sm(58628)/47409417156	282023	Youcef Lemsafer	06/2026
1757	2^936716-1835519	281980	Enzo Doria	04/2015
1758	2^936588+79411	281942	Enzo Doria	06/2016
1759	2^936047+1877423	281779	Enzo Doria	08/2016
1760	2^935713+1869377	281678	Enzo Doria	05/2016
1761	2^933082+1877059	280886	Enzo Doria	08/2016
1762	(5*10^280710+1)/3	280711	Serge Batalov	10/2014
1763	2^932443+225893	280694	Enzo Doria	08/2024
1764	2^932064+26521	280580	Enzo Doria	12/2023
1765	2^931976+25	280553	Stefano Morozzi	05/2021
1766	(42^172663+1)/43	280274	Paul Bourdelais	07/2019
1767	(10^279978+11)/3	279978	Serge Batalov	07/2015
1768	2^929524-1864829	279815	Enzo Doria	01/2016
1769	2^929329+22697	279756	Enzo Doria	09/2023
1770	2^929152+60181	279703	Enzo Doria	02/2016
1771	2^928621-2787883	279543	Enzo Doria	11/2015
1772	(2^927763+lucasV(-1,2,927763)+1)/2	279285	Mike Oakes	04/2017
1773	3*10^279271+77	279272	Robert Price	06/2024
1774	2^927429+1882277	279184	Enzo Doria	12/2016
1775	2^926766-11	278985	Stefano Morozzi	07/2022
1776	(71^150697-1)/70	278978	Paul Bourdelais	07/2019
1777	(33^183661-1)/32	278891	Paul Bourdelais	12/2018
1778	(5347*26^197061-297)/25	278839	Eric Chen	12/2025
1779	(166*10^278633-7)/3	278635	Robert Price	02/2023
1780	(2^925391+lucasV(-1,2,925391)+1)/2	278571	Mike Oakes	03/2017
1781	2^925330-1301	278553	Yves Minet	06/2015
1782	(299*10^278546+1)/3	278548	Robert Price	01/2023
1783	2^925299+216053	278543	Enzo Doria	11/2023
1785	(21^210599+1)/22	278457	Paul Bourdelais	08/2013
1784	(79^146749-1)/6395645198026062186	278457	Paul Vanderveen	06/2025
1786	(266*10^278325+1)/3	278327	Robert Price	01/2023
1787	2^923261-69175	277930	Enzo Doria	11/2015
1788	757^96487-756^96487	277796	Jean-Louis Charton	12/2012
1789	2^922301+57	277641	Stefano Morozzi	05/2021
1790	7*10^277478-39	277479	Robert Price	07/2023
1791	((((((((((((((291487327^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2)^2-2	277369	Serge Batalov	07/2016
1792	(5^396413-1)/4	277081	Paul Bourdelais	06/2010
1793	2^920318+2792299	277044	Enzo Doria	02/2016
1794	(16*10^276537-31)/3	276538	Robert Price	03/2023
1795	2^918596-2786939	276525	Enzo Doria	11/2015
1796	2^917910+28369	276319	Enzo Doria	01/2024
1797	2^917328+228571	276144	Enzo Doria	11/2024
1798	(6737^72361-1)/(6737^269-1)	276002	Ryan Propper	11/2023
1799	2^916639+60563	275936	Enzo Doria	04/2016
1800	(2*10^275922+1)/3	275922	Serge Batalov	11/2022
1801	2^916385-2786383	275860	Enzo Doria	11/2015
1802	2^915928+82081	275722	Enzo Doria	09/2016
1803	(4*10^275671+11)/3	275672	Tyler Busby	02/2023
1804	2^915576-114137	275616	Enzo Doria	01/2015
1805	2^914828+1876741	275391	Enzo Doria	07/2016
1806	2^914757-2203	275370	Yves Minet	12/2015
1807	7*10^275157-27	275158	Robert Price	11/2022
1808	2^912744+20011	274764	Enzo Doria	06/2023
1809	2^911900+1871245	274510	Enzo Doria	05/2016
1810	(16*10^274251-91)/3	274252	Robert Price	11/2022
1811	2^910999+9	274239	Stefano Morozzi	05/2021
1812	(2^910869-7)/5	274199	Stefano Morozzi	08/2022
1813	2^910490+283429	274085	Enzo Doria	01/2017
1814	7*10^273983+39	273984	Robert Price	01/2023
1815	2^909988-1862249	273934	Enzo Doria	12/2015
1816	2^909901+378567	273908	Boyan Hu	08/2024
1817	2^909297+1879157	273726	Enzo Doria	08/2016
1818	2^909257-1864423	273714	Enzo Doria	01/2016
1819	2^909254+31309	273713	Enzo Doria	03/2024
1820	2^908739-7	273558	Stefano Morozzi	07/2022
1821	2^908579-1861747	273510	Enzo Doria	12/2015
1822	3*2^908005-5	273338	Jon Grantham	07/2023
1823	2^907635-2791597	273226	Enzo Doria	01/2016
1824	2^907059+211193	273052	Enzo Doria	08/2023
1825	(53^158341+1)/54	273022	Paul Bourdelais	07/2019
1826	2^906594-113201	272912	Enzo Doria	08/2014
1827	9*10^272800+91	272801	Robert Price	05/2023
1828	2*10^272710-49	272711	Robert Price	05/2023
1829	2*10^272403-91	272404	Robert Price	02/2023
1830	2^904773+1872167	272364	Enzo Doria	06/2016
1831	6^349903+5	272278	Paul Bourdelais	02/2021
1832	2^904149-1862473	272176	Enzo Doria	12/2015
1833	2^902926+227839	271808	Enzo Doria	10/2024
1834	(7*10^271757-61)/9	271757	Erik Branger	03/2012
1835	2^902497+1880117	271679	Enzo Doria	09/2016
1836	2^901858+77689	271487	Enzo Doria	06/2016
1837	2^901372+1875301	271341	Enzo Doria	06/2016
1838	2^901146+219049	271272	Enzo Doria	02/2024
1839	(8*10^271039-77)/3	271040	Robert Price	04/2023
1840	2^899999+1144031	270927	Norman Luhn	09/2023
1841	2*10^270802-91	270803	Robert Price	02/2023
1842	23*10^270799-7	270801	Robert Price	10/2022
1843	(710^(2135371+1)-9*10^135371-7)/9	270743	Robert Price	06/2026
1844	2^899121-115033	270663	Enzo Doria	07/2015
1845	2^898900+883021	270596	Enzo Doria	12/2016
1846	2^898762-251511	270555	Enzo Doria	12/2013
1847	2^898589+47	270503	Lelio R Paula	03/2016
1848	(939628*10^270345-93962791)/9	270351	Danilo Nitsche	03/2026
1849	1447184*10^270344-14471839	270351	Danilo Nitsche	03/2026
1850	(3178852*10^270344-31788517)/3	270351	Danilo Nitsche	06/2026
1851	(5480939*10^270344-54809387)/3	270351	Danilo Nitsche	09/2026
1852	(4685483*10^270344-46854827)/3	270351	Danilo Nitsche	09/2026
1853	(4870196*10^270344-48701957)/3	270351	Danilo Nitsche	09/2026
1854	(5099635*10^270344-50996347)/3	270351	Danilo Nitsche	09/2026
1855	10400014*10^270343-10400013	270351	Danilo Nitsche	09/2026
1856	(9312289*10^270344-93122881)/9	270351	Danilo Nitsche	09/2026
1857	(9536569*10^270344-95365681)/9	270351	Danilo Nitsche	09/2026
1858	269048*10^270344-2690479	270350	Danilo Nitsche	02/2026
1859	172249*10^270344-1722489	270350	Danilo Nitsche	02/2026
1860	(288964*10^270345-28896397)/3	270350	Danilo Nitsche	02/2026
1861	661681*10^270344-6616809	270350	Danilo Nitsche	02/2026
1862	184489*10^270344-1844889	270350	Danilo Nitsche	02/2026
1863	58552*10^270345-5855199	270350	Danilo Nitsche	02/2026
1864	(245662*10^270345-24566197)/3	270350	Danilo Nitsche	02/2026
1865	371745*10^270344-3717449	270350	Danilo Nitsche	02/2026
1866	(1366645*10^270344-13666441)/9	270350	Danilo Nitsche	03/2026
1867	(1648732*10^270344-16487317)/3	270350	Danilo Nitsche	03/2026
1868	(1386601*10^270344-13866001)/9	270350	Danilo Nitsche	03/2026
1869	(1631944*10^270344-16319431)/9	270350	Danilo Nitsche	03/2026
1870	922284*10^270344-9222839	270350	Danilo Nitsche	03/2026
1871	992761*10^270344-9927609	270350	Danilo Nitsche	03/2026
1872	(2241127*10^270344-22411267)/3	270350	Danilo Nitsche	04/2026
1873	(2466128*10^270344-24661277)/3	270350	Danilo Nitsche	04/2026
1874	2366042*10^270343-2366041	270350	Danilo Nitsche	04/2026
1875	(2878615*10^270344-28786147)/3	270350	Danilo Nitsche	04/2026
1876	(2026252*10^270344-20262517)/3	270350	Danilo Nitsche	04/2026
1877	1967284*10^270343-1967283	270350	Danilo Nitsche	04/2026
1878	2629838*10^270343-2629837	270350	Danilo Nitsche	04/2026
1879	(2737132*10^270344-27371317)/3	270350	Danilo Nitsche	04/2026
1880	(4295404*10^270343-4295401)/3	270350	Danilo Nitsche	06/2026
1881	(3080173*10^270344-30801721)/9	270350	Danilo Nitsche	06/2026
1882	4452574*10^270343-4452573	270350	Danilo Nitsche	06/2026
1883	(4731721*10^270344-47317201)/9	270350	Danilo Nitsche	09/2026
1884	(5101564*10^270343-5101561)/3	270350	Danilo Nitsche	09/2026
1885	6873014*10^270343-6873013	270350	Danilo Nitsche	09/2026
1886	8009164*10^270343-8009163	270350	Danilo Nitsche	09/2026
1887	6811214*10^270343-6811213	270350	Danilo Nitsche	09/2026
1888	(6840172*10^270343-6840169)/3	270350	Danilo Nitsche	09/2026
1889	(7458736*10^270343-7458733)/3	270350	Danilo Nitsche	09/2026
1890	(7325554*10^270343-7325551)/3	270350	Danilo Nitsche	09/2026
1891	(6618056*10^270343-6618053)/3	270350	Danilo Nitsche	09/2026
1892	(6766564*10^270344-67665631)/9	270350	Danilo Nitsche	09/2026
1893	(7716208*10^270344-77162071)/9	270350	Danilo Nitsche	09/2026
1894	9468988*10^270343-9468987	270350	Danilo Nitsche	09/2026
1895	(9334978*10^270343-9334969)/9	270350	Danilo Nitsche	09/2026
1896	(9047482*10^270343-9047479)/3	270350	Danilo Nitsche	09/2026
1899	187322*10^270343-187321	270349	Danilo Nitsche	09/2013
1897	(4004452*10^270343-4004443)/9	270349	Danilo Nitsche	06/2026
1898	(8137012*10^270343-8137003)/9	270349	Danilo Nitsche	09/2026
1900	48358*10^270343-48357	270348	Danilo Nitsche	09/2013
1901	(10^270343-1)/9	270343	Maksym Voznyy	07/2007
1902	2^897867-3217	270285	Yves Minet	12/2016
1903	2^897849-115273	270280	Enzo Doria	07/2015
1904	2^897367+26289	270135	Enzo Doria	03/2024
1905	2^896616-114179	269909	Enzo Doria	12/2014
1906	(12648^66049-1)/(12648^257-1)	269881	Ryan Propper	11/2023
1907	(10^(2134811+1)+610^134811-1)/3	269623	Robert Price	08/2024
1908	(22*10^269517-19)/3	269518	Robert Price	07/2023
1909	10^(2134739+1)-710^134739-1	269479	Robert Price	07/2023
1910	2^894928+583561	269401	Enzo Doria	04/2017
1911	2^894673-39343	269324	Enzo Doria	08/2015
1912	2^893836+23221	269072	Enzo Doria	10/2023
1913	2^892718+29539	268735	Enzo Doria	03/2024
1914	2^892660+213901	268718	Enzo Doria	10/2023
1915	F(1285607)	268676	Henri Lifchitz	11/2008
1916	2^892234+22189	268590	Enzo Doria	09/2023
1917	2^892151+24863	268565	Enzo Doria	11/2023
1918	2^892112+187663	268553	Enzo Doria	08/2016
1919	(266*10^268407-17)/3	268409	Robert Price	02/2023
1920	(10^268207+1)/11	268206	Paul Bourdelais	02/2010
1921	2^890957-69583	268205	Enzo Doria	12/2015
1922	32841!^2+32840!^2+...+2!^2+1!^2	268128	Serge Batalov	07/2017
1923	2^890122-351401	267954	Enzo Doria	07/2015
1924	(19^209359-1)/18	267718	Paul Bourdelais	08/2010
1925	2^888852+229051	267572	Enzo Doria	11/2024
1926	(85^138647+1)/86	267507	Paul Bourdelais	07/2019
1927	(1005^89087-1)/1004	267451	Jinyuan Wang	01/2024
1928	(485^99523-1)/484	267291	Michael Stocker	05/2020
1929	2^886324+77791	266811	Enzo Doria	06/2016
1930	7*10^266731+87	266732	Robert Price	11/2022
1931	2^886040+213901	266725	Enzo Doria	10/2023
1932	2^885242+217909	266485	Enzo Doria	01/2024
1933	2^884738+26809	266333	Enzo Doria	12/2023
1934	2^884714+1880527	266326	Enzo Doria	10/2016
1935	7*10^266024-47	266025	Robert Price	08/2023
1936	11^255426+255426^11	265999	Serge Batalov	05/2014
1937	2^883462-343421	265949	Enzo Doria	07/2015
1938	2^883442+1875019	265943	Enzo Doria	06/2016
1939	2^883333-291583	265910	Enzo Doria	07/2015
1940	2^883132+30421	265850	Enzo Doria	03/2024
1941	10^265566+3593037	265567	Paul Bourdelais	08/2023
1942	(2*10^265321-17)/3	265321	Serge Batalov	11/2022
1943	(16*10^265052-91)/3	265053	Robert Price	11/2022
1944	2^880411+1882673	265031	Enzo Doria	12/2016
1945	2^880101+228917	264937	Enzo Doria	11/2024
1946	(14*10^264791-11)/3	264792	Robert Price	08/2022
1947	2^879530-2788031	264765	Enzo Doria	12/2015
1948	2^879292+25171	264694	Enzo Doria	11/2023
1949	(2*10^264539+61)/9	264539	Serge Batalov	11/2022
1950	2^878118+2793079	264340	Enzo Doria	02/2016
1951	(2^878073-7)/5	264326	Stefano Morozzi	08/2022
1952	(37^168527-1)/36	264283	Paul Bourdelais	08/2019
1953	5^377865+3^377865-1	264117	Jon Grantham	08/2023
1954	(19*10^263971+131)/3	263972	Robert Price	08/2023
1955	2^876202-17	263764	Stefano Morozzi	07/2022
1956	(14*10^263720-11)/3	263721	Robert Price	08/2022
1957	2^875748-461129	263627	Enzo Doria	07/2015
1958	2^875518-15	263558	Stefano Morozzi	07/2022
1959	(29*10^263523-17)/3	263524	Robert Price	01/2023
1960	2^875181-2789923	263456	Enzo Doria	12/2015
1961	2^875101-350083	263432	Enzo Doria	08/2015
1962	2^874684+1883587	263307	Enzo Doria	01/2017
1963	2^874616+1872211	263286	Enzo Doria	05/2016
1964	2^874566+30049	263271	Enzo Doria	03/2024
1965	3^551491+16	263129	Robert Price	04/2020
1966	2^874073+2792957	263123	Enzo Doria	02/2016
1967	(7*10^263006-19)/3	263007	Robert Price	10/2023
1968	2^873628+1878751	262989	Enzo Doria	08/2016
1969	2^873497+20837	262949	Enzo Doria	08/2023
1970	2^873288-269	262886	Yves Minet	01/2015
1971	(2*10^262874+7)/9	262874	Rytis Slatkevicius	01/2023
1972	(28*10^262655-43)/3	262656	Robert Price	04/2023
1973	(2*10^262603-11)/9	262603	Serge Batalov	11/2022
1974	2^871991-4207	262496	Yves Minet	03/2021
1975	(23*10^262324+7)/3	262325	Robert Price	05/2023
1976	2^871146-3173	262242	Yves Minet	07/2016
1977	(10^(2131020+1)+6310^131020-1)/9	262041	Robert Price	08/2024
1978	2^869601-163	261776	Yves Minet	01/2015
1979	(2*10^261704+61)/9	261704	Serge Batalov	11/2022
1980	2^869326+282859	261694	Enzo Doria	11/2016
1981	2^869035-114181	261606	Enzo Doria	12/2014
1982	2^868817+26777	261540	Enzo Doria	12/2023
1983	3^547850+9000004	261391	Enzo Doria	10/2023
1984	Phi(156793,2^7)	261261	Henri Lifchitz	10/2025
1985	4*10^261248+91	261249	Robert Price	11/2022
1986	55083^55083+1282^1282	261150	Henri Lifchitz	10/2024
1987	2^866908+34891	260966	Enzo Doria	07/2024
1988	2^865715+80303	260607	Enzo Doria	07/2016
1989	2^865474+23209	260534	Enzo Doria	10/2023
1990	2^865238+214759	260463	Enzo Doria	11/2023
1991	2^865048+1882411	260406	Enzo Doria	12/2016
1992	2^864899-113871	260361	Enzo Doria	10/2014
1993	(16*10^260256-91)/3	260257	Robert Price	11/2022
1994	(7*10^260198-61)/9	260198	Erik Branger	11/2011
1995	2^864298-2788421	260180	Enzo Doria	12/2015
1996	2^864039-2791357	260102	Enzo Doria	01/2016
1997	2^863621-113833	259976	Enzo Doria	10/2014
1998	10^259945-11	259945	Mischa Rodermond	04/2023
1999	2^863433+34877	259920	Enzo Doria	07/2024
2000	(28*10^259897+113)/3	259898	Robert Price	06/2023

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