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	2^1373958+42649	413603	Enzo Doria	02/2025
752	2^1373111+1884833	413348	Enzo Doria	02/2017
753	2^1372996+15	413313	Stefano Morozzi	10/2022
754	2^1372515+32393	413169	Enzo Doria	05/2024
755	2^1372092+228751	413041	Enzo Doria	11/2024
756	2^1372033+238427	413024	Enzo Doria	07/2025
757	2^1370877+38747	412676	Enzo Doria	11/2024
758	2^1369291+40943	412198	Enzo Doria	02/2025
759	2^1369207+36833	412173	Enzo Doria	10/2024
760	2^1369171+216593	412162	Enzo Doria	01/2024
761	2^1368632+1889731	412000	Enzo Doria	10/2017
762	(65245^85849-1)/(65245^293-1)	411914	Ryan Propper	11/2023
763	(89*10^411590+1)/9	411591	Serge Batalov	09/2014
764	F(1968721)	411439	Henri Lifchitz	11/2009
765	2^1366066+683749	411227	Enzo Doria	02/2017
766	2^1365324+233341	411004	Enzo Doria	03/2025
767	2^1365077+228257	410930	Enzo Doria	11/2024
768	2^1364401+217727	410726	Enzo Doria	02/2024
769	2^1364303+219533	410697	Enzo Doria	03/2024
770	2^1363434+27589	410435	Enzo Doria	02/2024
771	2^1363068+222631	410325	Enzo Doria	06/2024
772	2^1359550+25819	409266	Enzo Doria	12/2023
773	2^1359515+236423	409255	Enzo Doria	05/2025
774	2^1357392+224401	408616	Enzo Doria	06/2024
775	2^1355826+15	408145	Stefano Morozzi	10/2022
776	2^1355790+1888939	408134	Enzo Doria	07/2017
777	2^1355635+1884203	408087	Enzo Doria	01/2017
778	(22071^94249-1)/(22071^307-1)	408068	Ryan Propper	11/2023
779	2^1355083+221603	407921	Enzo Doria	05/2024
780	2^1355041+239777	407908	Enzo Doria	08/2025
781	2^1351989+36587	406990	Enzo Doria	09/2024
782	2^1351675+231083	406895	Enzo Doria	02/2025
783	2^1349535+218783	406251	Enzo Doria	03/2024
784	(55766^85849-1)/(55766^293-1)	406081	Ryan Propper	11/2023
785	2^1348956+24241	406077	Enzo Doria	11/2023
786	(88^208739+1)/89	405888	Paul Bourdelais	12/2020
787	(2^1347781-2^673891+1)/5	405722	Borys Jaworski	10/2008
788	2^1347744-3	405712	Paul Bourdelais	07/2019
789	2^1347546+39133	405652	Enzo Doria	12/2024
790	2^1346431+691203	405317	Boyan Hu	09/2024
791	82358^82358+2025^2025	404848	Henri Lifchitz	01/2025
792	9*10^404644-11	404645	Mischa Rodermond	04/2023
793	2^1343509+237947	404437	Enzo Doria	07/2025
794	1215^131072+242^131072	404302	Kellen Shenton	08/2022
795	2^1341908+212911	403955	Enzo Doria	09/2023
796	2^1341625+226187	403870	Enzo Doria	09/2024
797	2^1340284+43801	403466	Enzo Doria	04/2025
798	1196^131072+595^131072	403405	Kellen Shenton	08/2022
799	2^1339302+29389	403171	Enzo Doria	04/2024
800	2^1335130+31669	401915	Enzo Doria	07/2024
801	2^1333062+236449	401292	Enzo Doria	07/2025
802	2^1330791+46763	400609	Enzo Doria	06/2025
803	2^1330712+45631	400585	Enzo Doria	05/2025
804	2^1330388+38527	400487	Enzo Doria	11/2024
805	2^1330371+28313	400482	Enzo Doria	03/2024
806	10^400310+9	400311	Boyan Hu	06/2025
807	10^400000+1415223	400001	Patrick De Geest	10/2020
808	10^400000-339233	400000	Patrick De Geest	10/2020
809	2^1327766+48019	399698	Enzo Doria	06/2025
810	2^1323373+27317	398375	Enzo Doria	01/2024
811	Tau(863^24630)	397727	Nik Lygeros / Olivier Rozier	01/2016
812	2^1320423+24293	397487	Enzo Doria	11/2023
813	2^1320057+211517	397377	Enzo Doria	08/2023
814	2^1319770+1884949	397291	Enzo Doria	06/2017
815	2^1319616+30091	397244	Enzo Doria	04/2024
816	2^1317657+31367	396655	Enzo Doria	04/2024
817	2^1316848+43021	396411	Enzo Doria	02/2025
818	2^1316687+45983	396363	Enzo Doria	05/2025
819	2^1315753+226187	396082	Enzo Doria	09/2024
820	2^1314741+219257	395777	Enzo Doria	03/2024
821	2^1313062+1888849	395272	Enzo Doria	08/2017
822	(1073516^81920+1)/(1073516^16384+1)	395236	Serge Batalov	01/2017
823	2^1312349+221177	395057	Enzo Doria	04/2024
824	(1059995^81920+1)/(1059995^16384+1)	394875	Serge Batalov	01/2017
825	2^1311618+783529	394837	Enzo Doria	01/2017
826	2^1310192+232531	394408	Enzo Doria	03/2025
827	2^1308992+28111	394046	Enzo Doria	02/2024
828	2^1308000+1883521	393748	Enzo Doria	02/2017
829	2^1307563+232133	393616	Enzo Doria	03/2025
830	2^1307324+224611	393544	Enzo Doria	07/2024
831	2^1307262+28759	393526	Enzo Doria	02/2024
832	(1009565^81920+1)/(1009565^16384+1)	393487	Serge Batalov	01/2017
833	2^1306643+47333	393339	Enzo Doria	07/2025
834	2^1305860+35461	393104	Enzo Doria	08/2024
835	(995042^81920+1)/(995042^16384+1)	393075	Serge Batalov	01/2017
836	2^1305333+47717	392945	Enzo Doria	06/2025
837	(988945^81920+1)/(988945^16384+1)	392900	Serge Batalov	01/2017
838	(988823^81920+1)/(988823^16384+1)	392897	Serge Batalov	01/2017
839	(2^1304983-1)/52199321	392832	Tony Prest / Never Odd Or Even	03/2014
840	(978970^81920+1)/(978970^16384+1)	392612	Serge Batalov	01/2017
841	2^1303816+38251	392488	Enzo Doria	11/2024
842	2^1303257+48527	392320	Enzo Doria	07/2025
843	2^1303102+1866409	392273	Enzo Doria	09/2017
844	2^1302818+283429	392188	Enzo Doria	01/2017
845	2^1301430+22669	391770	Enzo Doria	10/2023
846	2^1301229+222467	391709	Enzo Doria	04/2024
847	2^1300835+232523	391591	Enzo Doria	03/2025
848	(934422^81920+1)/(934422^16384+1)	391286	Serge Batalov	01/2017
849	2^1299181+1886867	391093	Enzo Doria	04/2017
850	(37^249341-1)/36	391016	Paul Bourdelais	08/2020
851	2^1298304+1882891	390829	Enzo Doria	01/2017
852	2^1297732+228721	390657	Enzo Doria	11/2024
853	95196^12497+12497^95196	390000	Hans Havermann	12/2021
854	2^1295539+35633	389997	Enzo Doria	08/2024
855	86206^33381+33381^86206	389953	Hans Havermann	05/2023
856	2^1294976+236731	389827	Enzo Doria	06/2025
857	2^1294324+25171	389631	Enzo Doria	12/2023
858	(874207^81920+1)/(874207^16384+1)	389390	Serge Batalov	01/2017
859	2^1292338+229249	389033	Enzo Doria	11/2024
860	2^1289624+32551	388216	Enzo Doria	05/2024
861	2^1286857+37967	387383	Enzo Doria	10/2024
862	2^1285458+46159	386962	Enzo Doria	06/2025
863	2^1285456+230611	386961	Enzo Doria	01/2025
864	(7^457871-5^457871)/2	386946	Jon Grantham	08/2023
865	79455^73828+73828^79455	386805	Hans Havermann	03/2023
866	81650^54369+54369^81650	386642	Yusuf AttarBashi	06/2021
867	80565^62824+62824^80565	386561	Hans Havermann	08/2021
868	83747^41272+41272^83747	386548	Hans Havermann	08/2021
869	15^328574+328574^15	386434	Serge Batalov	05/2014
870	2^1282676+30493	386124	Enzo Doria	12/2024
871	2^1280078+1885099	385342	Enzo Doria	08/2017
872	2^1279921+17	385295	Stefano Morozzi	10/2022
873	2^1279245+224087	385092	Enzo Doria	07/2024
874	2^1278091+47963	384744	Enzo Doria	07/2025
875	2^1277980+231391	384711	Enzo Doria	01/2025
876	2^1277688+231241	384623	Enzo Doria	01/2025
877	2^1277142+234979	384459	Enzo Doria	04/2025
878	2^1276977+71657	384409	Enzo Doria	08/2023
879	(76803^78961-1)/(76803^281-1)	384382	Ryan Propper	11/2023
880	2^1276571+26213	384287	Enzo Doria	12/2023
881	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
882	2^1274941+1880717	383796	Enzo Doria	10/2016
883	2^1272632+383431	383101	Enzo Doria	01/2017
884	2^1271346+1889839	382714	Enzo Doria	08/2017
885	2^1271173+219587	382662	Enzo Doria	03/2024
886	5*3^798534-2^798534	380999	Jon Grantham	08/2023
887	(10^380976-7)/3	380976	Leonid Durman	01/2012
888	2^1264748+23221	380728	Enzo Doria	11/2023
889	(4*10^380056+11)/3	380057	Tyler Busby	03/2023
890	2^1262431+228353	380030	Enzo Doria	11/2024
891	2^1260859+222683	379557	Enzo Doria	06/2024
892	2^1258313+43727	378790	Enzo Doria	03/2025
893	2^1257787+1447761	378632	Makoto Morimoto	10/2013
894	(2^1257787+32270)/(223328122073011)	378620	Makoto Morimoto	12/2016
895	2^1257728+20851	378614	Enzo Doria	08/2023
896	(77^200657-1)/76	378536	Paul Bourdelais	08/2020
897	2^1257107+45413	378427	Enzo Doria	05/2025
898	2^1254797+229487	377732	Enzo Doria	11/2024
899	(98^189619+1)/99	377573	Paul Bourdelais	02/2021
900	F(1803059)	376817	Henri Lifchitz	06/2009
901	2^1250590+29389	376466	Enzo Doria	03/2024
902	(10^376417-3^376417)/7	376417	Jon Grantham	08/2023
903	2^1250116+34951	376323	Enzo Doria	08/2024
904	2^1246724+213961	375302	Enzo Doria	10/2023
905	2^1245610+237919	374966	Enzo Doria	06/2025
906	2^1245230+19	374852	Stefano Morozzi	10/2022
907	2^1244263+230033	374561	Enzo Doria	01/2025
908	7^442674+4	374103	Paul Bourdelais	02/2021
909	2^1242268+239641	373960	Enzo Doria	08/2025
910	2^1239151+35633	373022	Enzo Doria	08/2024
911	2^1238732+39181	372896	Enzo Doria	11/2024
912	2^1237699+34703	372585	Enzo Doria	07/2024
913	(97^187393-1)/96	372306	Paul Bourdelais	09/2020
914	2^1235070+46219	371794	Enzo Doria	05/2025
915	10^371696+7	371697	Alfred Reich	05/2021
916	2^1234709+883127	371685	Enzo Doria	12/2016
917	2^1234688+237151	371679	Enzo Doria	08/2025
918	2^1234119+21803	371507	Enzo Doria	09/2023
919	(67^203431+1)/68	371479	Paul Bourdelais	09/2021
920	2^1233971+216593	371463	Enzo Doria	12/2023
921	2^1233212+27301	371234	Enzo Doria	12/2023
922	2^1231529+237557	370728	Enzo Doria	06/2025
923	2^1231466+283819	370709	Enzo Doria	07/2017
924	2^1229766+26659	370197	Enzo Doria	12/2023
925	2^1228899+30713	369936	Enzo Doria	03/2024
926	2^1228892+223831	369934	Enzo Doria	06/2024
927	2^1227635+45413	369555	Enzo Doria	05/2025
928	(49627^78961-1)/(49627^281-1)	369460	Ryan Propper	11/2023
929	2^1227060+226663	369382	Enzo Doria	09/2024
930	2^1226987+28163	369360	Enzo Doria	02/2024
931	2^1226725+234887	369282	Enzo Doria	04/2025
932	2^1226569+30857	369235	Enzo Doria	03/2024
933	2^1225268+46591	368843	Enzo Doria	05/2025
934	73^197880+197880	368715	Kellen Shenton	06/2023
935	5*3^771723-2^771723	368207	Jon Grantham	08/2023
936	2^1222741+231707	368082	Enzo Doria	02/2025
937	2^1222473+221597	368002	Enzo Doria	04/2024
938	2^1222211+22703	367923	Enzo Doria	11/2023
939	(2^1222097+19)/3	367888	Stefano Morozzi	09/2022
940	2^1220335+1881263	367358	Enzo Doria	11/2016
941	2^1218344+215641	366759	Enzo Doria	12/2023
942	2^1217510+220039	366508	Enzo Doria	03/2024
943	2^1217500+226321	366505	Enzo Doria	09/2024
944	(233^154787-1)/232	366434	Anonymous	05/2024
945	2^1216694+1884769	366262	Enzo Doria	02/2017
946	2^1216267+45143	366133	Enzo Doria	05/2025
947	2^1215889-3	366020	Paul Bourdelais	06/2019
948	2^1215296+1885441	365841	Enzo Doria	03/2017
949	(80^192133+1)/81	365645	Paul Bourdelais	01/2021
950	2^1214307+1888115	365543	Enzo Doria	05/2017
951	2^1213815+3	365395	Paul Bourdelais	06/2019
952	(80^191953+1)/81	365302	Paul Bourdelais	01/2021
953	2^1213313+215837	365244	Enzo Doria	11/2023
954	2^1208276+22201	363728	Enzo Doria	09/2023
955	2^1207345+1882577	363448	Enzo Doria	12/2016
956	2^1207336+217801	363445	Enzo Doria	03/2024
957	2^1207073+883727	363366	Enzo Doria	03/2017
958	3^761457-2	363308	Ryan Propper	07/2015
959	(10^363030+7)/337/443	363025	Alfred Reich	12/2021
960	2^1204869+224885	362702	Enzo Doria	07/2024
961	2^1204540+237541	362603	Enzo Doria	07/2025
962	2^1203721+44117	362357	Enzo Doria	04/2025
963	2^1200972+141811	361529	Stefano Morozzi	10/2022
964	(2^1200924+324730)/2	361514	Stefano Morozzi	06/2021
965	(2^1200912+274110)/2	361511	Stefano Morozzi	01/2021
966	2^1200906+165249	361509	Stefano Morozzi	07/2022
967	2^1200890+166339	361504	Stefano Morozzi	01/2023
968	(2^1200887+344126)/2	361503	Stefano Morozzi	10/2020
969	2^1200877+186755	361500	Stefano Morozzi	09/2022
970	2^1200861+198521	361496	Stefano Morozzi	11/2021
971	(2^1200856+305790)/2	361494	Stefano Morozzi	10/2020
972	(2^1200853+372822)/2	361493	Stefano Morozzi	06/2021
973	2^1200812+324178)/2	361481	Stefano Morozzi	06/2021
974	(2^1200768+380458)/2	361467	Stefano Morozzi	01/2021
975	2^1200756+140917	361464	Stefano Morozzi	05/2022
976	2^1200741+184781	361460	Stefano Morozzi	09/2022
977	(2^1200741+293402)/2	361459	Stefano Morozzi	07/2021
978	2^1200734+142653	361457	Stefano Morozzi	02/2023
980	2^1200672+1880881	361439	Enzo Doria	10/2016
979	2^1200672+141535	361439	Stefano Morozzi	09/2022
981	2^1200669+178805	361438	Stefano Morozzi	11/2022
982	2^1200660+198555	361435	Stefano Morozzi	12/2021
983	2^1200657+164837	361434	Stefano Morozzi	05/2022
984	2^1200631+166431	361426	Stefano Morozzi	02/2023
985	2^1200627+150669	361425	Stefano Morozzi	02/2023
986	(2^1200603+356030)/2	361418	Stefano Morozzi	10/2020
987	(2^1200590+275854)/2	361414	Stefano Morozzi	03/2021
988	2^1200550+139297	361402	Stefano Morozzi	10/2021
989	2^1200486+172855	361383	Stefano Morozzi	01/2023
990	(2^1200456+320526)/2	361373	Stefano Morozzi	10/2020
991	2^1200443+142121	361370	Stefano Morozzi	01/2023
992	2^1200416+164065	361362	Stefano Morozzi	01/2022
993	2^1200331+155429	361336	Stefano Morozzi	10/2021
995	(2^1200289+348366)/2	361323	Stefano Morozzi	10/2020
994	2^1200289+141885	361323	Stefano Morozzi	11/2022
996	(2^1200284+273162)/2	361322	Stefano Morozzi	10/2020
997	2^1200252+194535	361312	Stefano Morozzi	11/2021
998	(2^1200250+364230)/2	361311	Stefano Morozzi	10/2020
999	2^1200227+156881	361305	Stefano Morozzi	05/2022
1000	(2^1200209+305990)/2	361299	Stefano Morozzi	10/2020

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