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 ?
751	2^1408670+238579	424052	Enzo Doria	09/2025
752	2^1408457+232007	423988	Enzo Doria	02/2025
753	2^1407208+45751	423612	Enzo Doria	06/2025
754	2^1406408+50371	423371	Enzo Doria	09/2025
755	2^1405715-1405715^2	423163	Henri Lifchitz	03/2025
756	1+3^605376+5^605376	423140	Jon Grantham	08/2023
757	2^1405367+213413	423058	Enzo Doria	10/2023
758	2^1404213+184217	422711	Enzo Doria	09/2017
759	2^1403156+40921	422393	Enzo Doria	02/2025
760	2^1401872+1884385	422006	Enzo Doria	04/2017
761	2^1401257+6077	421821	Enzo Doria	09/2017
762	2^1400648+44881	421638	Enzo Doria	05/2025
763	138^196873-137^196873	421285	Jean-Louis Charton	12/2009
764	2^1398726+7	421059	Stefano Morozzi	10/2022
765	2^1398269+131595	420921	Makoto Morimoto	10/2013
766	2^1398238+227119	420912	Enzo Doria	10/2024
767	2^1398062+40639	420859	Enzo Doria	01/2025
768	2^1398016+229357	420845	Enzo Doria	02/2025
769	2^1397089-1397089	420566	Henri Lifchitz	10/2024
770	2^1397071+684443	420561	Enzo Doria	07/2017
771	953^141023-952^141023	420121	Jean-Louis Charton	10/2016
772	2^1393449+45197	419470	Enzo Doria	05/2025
773	2^1393111+1867211	419369	Enzo Doria	09/2023
774	2^1392384+44371	419150	Enzo Doria	03/2025
775	2^1391771+36623	418965	Enzo Doria	09/2024
776	(3^877843-1)/2	418838	Paul Bourdelais	07/2010
777	2^1389628+28651	418320	Enzo Doria	03/2024
778	2^1389064+45751	418150	Enzo Doria	06/2025
779	2^1388780+50311	418065	Enzo Doria	09/2025
780	2^1386321+60299	417325	Enzo Doria	02/2018
781	2^1386320+184531	417324	Enzo Doria	09/2017
782	2^1382074+1883587	416046	Enzo Doria	01/2017
783	2^1380651+215843	415618	Enzo Doria	12/2023
784	2^1380634+40639	415613	Enzo Doria	01/2025
785	2^1379907+1885223	415394	Enzo Doria	03/2017
786	2^1379815+47333	415366	Enzo Doria	07/2025
787	2^1379792+45421	415359	Enzo Doria	06/2025
788	2^1379111+29693	415154	Enzo Doria	05/2024
789	2^1377927+45083	414798	Enzo Doria	06/2025
790	2^1377501+46427	414670	Enzo Doria	07/2025
791	2^1376707+25763	414431	Enzo Doria	12/2023
792	2^1375751+24443	414143	Enzo Doria	12/2023
793	2^1375574+1886719	414090	Enzo Doria	04/2017
794	2^1373958+42649	413603	Enzo Doria	02/2025
795	2^1373551+49343	413481	Enzo Doria	08/2025
796	2^1373111+1884833	413348	Enzo Doria	02/2017
797	2^1372996+15	413313	Stefano Morozzi	10/2022
798	2^1372515+32393	413169	Enzo Doria	05/2024
799	2^1372092+228751	413041	Enzo Doria	11/2024
800	2^1372033+238427	413024	Enzo Doria	07/2025
801	2^1370877+38747	412676	Enzo Doria	11/2024
802	2^1369291+40943	412198	Enzo Doria	02/2025
803	2^1369207+36833	412173	Enzo Doria	10/2024
804	2^1369171+216593	412162	Enzo Doria	01/2024
805	2^1368632+1889731	412000	Enzo Doria	10/2017
806	(65245^85849-1)/(65245^293-1)	411914	Ryan Propper	11/2023
807	(89*10^411590+1)/9	411591	Serge Batalov	09/2014
808	F(1968721)	411439	Henri Lifchitz	11/2009
809	2^1366066+683749	411227	Enzo Doria	02/2017
810	2^1365324+233341	411004	Enzo Doria	03/2025
811	2^1365077+228257	410930	Enzo Doria	11/2024
812	2^1364401+217727	410726	Enzo Doria	02/2024
813	2^1364303+219533	410697	Enzo Doria	03/2024
814	2^1363802+51169	410546	Enzo Doria	10/2025
815	2^1363434+27589	410435	Enzo Doria	02/2024
816	2^1363068+222631	410325	Enzo Doria	06/2024
817	2^1360101+51287	409432	Enzo Doria	10/2025
818	2^1359550+25819	409266	Enzo Doria	12/2023
819	2^1359515+236423	409255	Enzo Doria	05/2025
820	2^1357392+224401	408616	Enzo Doria	06/2024
821	2^1355826+15	408145	Stefano Morozzi	10/2022
822	2^1355790+1888939	408134	Enzo Doria	07/2017
823	2^1355635+1884203	408087	Enzo Doria	01/2017
824	(22071^94249-1)/(22071^307-1)	408068	Ryan Propper	11/2023
825	2^1355083+221603	407921	Enzo Doria	05/2024
826	2^1355041+239777	407908	Enzo Doria	08/2025
827	2^1351989+36587	406990	Enzo Doria	09/2024
828	2^1351675+231083	406895	Enzo Doria	02/2025
829	2^1349535+218783	406251	Enzo Doria	03/2024
830	(55766^85849-1)/(55766^293-1)	406081	Ryan Propper	11/2023
831	2^1348956+24241	406077	Enzo Doria	11/2023
832	(88^208739+1)/89	405888	Paul Bourdelais	12/2020
833	(2^1347781-2^673891+1)/5	405722	Borys Jaworski	10/2008
834	2^1347744-3	405712	Paul Bourdelais	07/2019
835	2^1347546+39133	405652	Enzo Doria	12/2024
836	2^1346431+691203	405317	Boyan Hu	09/2024
837	82358^82358+2025^2025	404848	Henri Lifchitz	01/2025
838	9*10^404644-11	404645	Mischa Rodermond	04/2023
839	2^1343509+237947	404437	Enzo Doria	07/2025
840	1215^131072+242^131072	404302	Kellen Shenton	08/2022
841	2^1341908+212911	403955	Enzo Doria	09/2023
842	2^1341625+226187	403870	Enzo Doria	09/2024
843	2^1340284+43801	403466	Enzo Doria	04/2025
844	2^1340172+240991	403432	Enzo Doria	10/2025
845	1196^131072+595^131072	403405	Kellen Shenton	08/2022
846	2^1339302+29389	403171	Enzo Doria	04/2024
847	2^1335130+31669	401915	Enzo Doria	07/2024
848	2^1333062+236449	401292	Enzo Doria	07/2025
849	2^1330791+46763	400609	Enzo Doria	06/2025
850	2^1330712+45631	400585	Enzo Doria	05/2025
851	2^1330388+38527	400487	Enzo Doria	11/2024
852	2^1330371+28313	400482	Enzo Doria	03/2024
853	10^400310+9	400311	Boyan Hu	06/2025
854	10^400000+1415223	400001	Patrick De Geest	10/2020
855	10^400000-339233	400000	Patrick De Geest	10/2020
856	2^1327766+48019	399698	Enzo Doria	06/2025
857	2^1323373+27317	398375	Enzo Doria	01/2024
858	Tau(863^24630)	397727	Nik Lygeros / Olivier Rozier	01/2016
859	2^1320423+24293	397487	Enzo Doria	11/2023
860	2^1320057+211517	397377	Enzo Doria	08/2023
861	2^1319770+1884949	397291	Enzo Doria	06/2017
862	2^1319616+30091	397244	Enzo Doria	04/2024
863	2^1317657+31367	396655	Enzo Doria	04/2024
864	2^1316848+43021	396411	Enzo Doria	02/2025
865	2^1316687+45983	396363	Enzo Doria	05/2025
866	2^1315753+226187	396082	Enzo Doria	09/2024
867	2^1314741+219257	395777	Enzo Doria	03/2024
868	2^1313062+1888849	395272	Enzo Doria	08/2017
869	(1073516^81920+1)/(1073516^16384+1)	395236	Serge Batalov	01/2017
870	2^1312349+221177	395057	Enzo Doria	04/2024
871	(1059995^81920+1)/(1059995^16384+1)	394875	Serge Batalov	01/2017
872	2^1311618+783529	394837	Enzo Doria	01/2017
873	2^1310192+232531	394408	Enzo Doria	03/2025
874	2^1308992+28111	394046	Enzo Doria	02/2024
875	2^1308000+1883521	393748	Enzo Doria	02/2017
876	2^1307563+232133	393616	Enzo Doria	03/2025
877	2^1307324+224611	393544	Enzo Doria	07/2024
878	2^1307262+28759	393526	Enzo Doria	02/2024
879	(1009565^81920+1)/(1009565^16384+1)	393487	Serge Batalov	01/2017
880	2^1306643+47333	393339	Enzo Doria	07/2025
881	2^1305860+35461	393104	Enzo Doria	08/2024
882	(995042^81920+1)/(995042^16384+1)	393075	Serge Batalov	01/2017
883	2^1305333+47717	392945	Enzo Doria	06/2025
884	(988945^81920+1)/(988945^16384+1)	392900	Serge Batalov	01/2017
885	(988823^81920+1)/(988823^16384+1)	392897	Serge Batalov	01/2017
886	(2^1304983-1)/52199321	392832	Tony Prest / Never Odd Or Even	03/2014
887	(978970^81920+1)/(978970^16384+1)	392612	Serge Batalov	01/2017
888	2^1303816+38251	392488	Enzo Doria	11/2024
889	2^1303257+48527	392320	Enzo Doria	07/2025
890	2^1303102+1866409	392273	Enzo Doria	09/2017
891	2^1302818+283429	392188	Enzo Doria	01/2017
892	2^1301430+22669	391770	Enzo Doria	10/2023
893	2^1301229+222467	391709	Enzo Doria	04/2024
894	2^1300835+232523	391591	Enzo Doria	03/2025
895	(934422^81920+1)/(934422^16384+1)	391286	Serge Batalov	01/2017
896	2^1299181+1886867	391093	Enzo Doria	04/2017
897	(37^249341-1)/36	391016	Paul Bourdelais	08/2020
898	2^1298304+1882891	390829	Enzo Doria	01/2017
899	2^1297732+228721	390657	Enzo Doria	11/2024
900	2^1295728+240751	390053	Enzo Doria	09/2025
901	95196^12497+12497^95196	390000	Hans Havermann	12/2021
902	2^1295539+35633	389997	Enzo Doria	08/2024
903	86206^33381+33381^86206	389953	Hans Havermann	05/2023
904	2^1294976+236731	389827	Enzo Doria	06/2025
905	2^1294324+25171	389631	Enzo Doria	12/2023
906	(874207^81920+1)/(874207^16384+1)	389390	Serge Batalov	01/2017
907	2^1292338+229249	389033	Enzo Doria	11/2024
908	2^1289624+32551	388216	Enzo Doria	05/2024
909	2^1286857+37967	387383	Enzo Doria	10/2024
910	2^1285458+46159	386962	Enzo Doria	06/2025
911	2^1285456+230611	386961	Enzo Doria	01/2025
912	(7^457871-5^457871)/2	386946	Jon Grantham	08/2023
913	79455^73828+73828^79455	386805	Hans Havermann	03/2023
914	81650^54369+54369^81650	386642	Yusuf AttarBashi	06/2021
915	80565^62824+62824^80565	386561	Hans Havermann	08/2021
916	83747^41272+41272^83747	386548	Hans Havermann	08/2021
917	15^328574+328574^15	386434	Serge Batalov	05/2014
918	2^1282676+30493	386124	Enzo Doria	12/2024
919	2^1280078+1885099	385342	Enzo Doria	08/2017
920	2^1279921+17	385295	Stefano Morozzi	10/2022
921	2^1279245+224087	385092	Enzo Doria	07/2024
922	2^1278091+47963	384744	Enzo Doria	07/2025
923	2^1277980+231391	384711	Enzo Doria	01/2025
924	2^1277688+231241	384623	Enzo Doria	01/2025
925	2^1277142+234979	384459	Enzo Doria	04/2025
926	2^1276977+71657	384409	Enzo Doria	08/2023
927	(76803^78961-1)/(76803^281-1)	384382	Ryan Propper	11/2023
928	2^1276571+26213	384287	Enzo Doria	12/2023
929	MillsLike(2,1,4,12,4,22,12,114,4,138,142,2956,6388,5248,17532,96930,83782,1464,897448,300832,26908)	384166	Sergey Batalov	05/2024
930	2^1274941+1880717	383796	Enzo Doria	10/2016
931	2^1272632+383431	383101	Enzo Doria	01/2017
932	2^1271346+1889839	382714	Enzo Doria	08/2017
933	2^1271173+219587	382662	Enzo Doria	03/2024
934	2^1266263+239783	381184	Enzo Doria	09/2025
935	5*3^798534-2^798534	380999	Jon Grantham	08/2023
936	(10^380976-7)/3	380976	Leonid Durman	01/2012
937	2^1264748+23221	380728	Enzo Doria	11/2023
938	(4*10^380056+11)/3	380057	Tyler Busby	03/2023
939	2^1262431+228353	380030	Enzo Doria	11/2024
940	2^1260859+222683	379557	Enzo Doria	06/2024
941	2^1258313+43727	378790	Enzo Doria	03/2025
942	2^1257787+1447761	378632	Makoto Morimoto	10/2013
943	(2^1257787+32270)/(223328122073011)	378620	Makoto Morimoto	12/2016
944	2^1257728+20851	378614	Enzo Doria	08/2023
945	(77^200657-1)/76	378536	Paul Bourdelais	08/2020
946	2^1257107+45413	378427	Enzo Doria	05/2025
947	2^1254797+229487	377732	Enzo Doria	11/2024
948	(98^189619+1)/99	377573	Paul Bourdelais	02/2021
949	Phi(17#,12492)	377546	Henri Lifchitz	10/2025
950	F(1803059)	376817	Henri Lifchitz	06/2009
951	2^1250590+29389	376466	Enzo Doria	03/2024
952	(10^376417-3^376417)/7	376417	Jon Grantham	08/2023
953	2^1250116+34951	376323	Enzo Doria	08/2024
954	2^1246724+213961	375302	Enzo Doria	10/2023
955	2^1245610+237919	374966	Enzo Doria	06/2025
956	2^1245230+19	374852	Stefano Morozzi	10/2022
957	2^1244263+230033	374561	Enzo Doria	01/2025
958	7^442674+4	374103	Paul Bourdelais	02/2021
959	2^1242374+240919	373992	Enzo Doria	09/2025
960	2^1242268+239641	373960	Enzo Doria	08/2025
961	2^1239151+35633	373022	Enzo Doria	08/2024
962	2^1238732+39181	372896	Enzo Doria	11/2024
963	2^1237699+34703	372585	Enzo Doria	07/2024
964	(97^187393-1)/96	372306	Paul Bourdelais	09/2020
965	2^1235070+46219	371794	Enzo Doria	05/2025
966	10^371696+7	371697	Alfred Reich	05/2021
967	2^1234709+883127	371685	Enzo Doria	12/2016
968	2^1234688+237151	371679	Enzo Doria	08/2025
969	2^1234119+21803	371507	Enzo Doria	09/2023
970	(67^203431+1)/68	371479	Paul Bourdelais	09/2021
971	2^1233971+216593	371463	Enzo Doria	12/2023
972	2^1233212+27301	371234	Enzo Doria	12/2023
973	2^1231529+237557	370728	Enzo Doria	06/2025
974	2^1231466+283819	370709	Enzo Doria	07/2017
975	2^1229766+26659	370197	Enzo Doria	12/2023
976	2^1228899+30713	369936	Enzo Doria	03/2024
977	2^1228892+223831	369934	Enzo Doria	06/2024
978	2^1227635+45413	369555	Enzo Doria	05/2025
979	(49627^78961-1)/(49627^281-1)	369460	Ryan Propper	11/2023
980	2^1227060+226663	369382	Enzo Doria	09/2024
981	2^1226987+28163	369360	Enzo Doria	02/2024
982	2^1226725+234887	369282	Enzo Doria	04/2025
983	2^1226569+30857	369235	Enzo Doria	03/2024
984	2^1225268+46591	368843	Enzo Doria	05/2025
985	73^197880+197880	368715	Kellen Shenton	06/2023
986	5*3^771723-2^771723	368207	Jon Grantham	08/2023
987	2^1222741+231707	368082	Enzo Doria	02/2025
988	2^1222473+221597	368002	Enzo Doria	04/2024
989	2^1222211+22703	367923	Enzo Doria	11/2023
990	(2^1222097+19)/3	367888	Stefano Morozzi	09/2022
991	2^1220335+1881263	367358	Enzo Doria	11/2016
992	2^1219561+47897	367125	Enzo Doria	09/2025
993	2^1219351+240773	367062	Enzo Doria	09/2025
994	2^1218344+215641	366759	Enzo Doria	12/2023
995	2^1217510+220039	366508	Enzo Doria	03/2024
996	2^1217500+226321	366505	Enzo Doria	09/2024
997	(233^154787-1)/232	366434	Anonymous	05/2024
998	2^1216694+1884769	366262	Enzo Doria	02/2017
999	2^1216267+45143	366133	Enzo Doria	05/2025
1000	2^1215889-3	366020	Paul Bourdelais	06/2019

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Probable Primes Top 10000

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