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 ?
2251	(19*10^224533-37)/9	224534	Alfred Reich	12/2023
2252	2^745674+213949	224471	Enzo Doria	10/2023
2253	2^745098-350471	224297	Enzo Doria	06/2015
2254	2^745039-4897	224280	Yves Minet	03/2021
2255	23*10^224232-7	224234	Robert Price	10/2022
2256	(154*10^224061-1)/9	224063	Serge Batalov	12/2014
2257	2^744211-1845787	224030	Enzo Doria	07/2015
2258	2^743773+37757	223898	Enzo Doria	10/2024
2259	2^743592-134579	223844	Hans Havermann	10/2018
2260	2^742452+3	223501	Paul Bourdelais	06/2019
2261	234178^9+9^234178	223463	Anatoly F. Selevich	07/2011
2262	47747^47747-2512^2512	223406	Henri Lifchitz	10/2024
2263	2^741651-461197	223260	Enzo Doria	07/2015
2264	10^223236-1001	223236	Robert Price	10/2022
2265	2^741362-1845251	223173	Enzo Doria	07/2015
2266	3^467546-5*2^467546	223077	Jon Grantham	08/2023
2267	2^740455-1863877	222900	Enzo Doria	12/2015
2268	2^740274+217519	222845	Enzo Doria	01/2024
2269	(14*10^222718-41)/9	222719	Serge Batalov	01/2023
2270	2^739636-2792219	222653	Enzo Doria	02/2016
2271	11^213654-180	222498	Enzo Doria	01/2013
2272	2^738957-1859743	222449	Enzo Doria	11/2015
2273	4*10^222253-21	222254	Robert Price	12/2022
2274	2^737825+57	222108	Stefano Morozzi	05/2021
2275	(54^128189+1)/55	222073	Paul Bourdelais	11/2018
2276	3^232689+1^232689+4^232689+1^232689+5^232689+9^232689	222042	Henri Lifchitz	03/2025
2277	2^737166+220099	221910	Enzo Doria	03/2024
2278	394^85431+393	221736	Alfred Reich	03/2026
2279	(10^221654+179)/9	221654	Serge Batalov	12/2014
2280	2^736281+79817	221643	Enzo Doria	06/2016
2281	10^221631+247617	221632	Patrick De Geest	10/2013
2282	10^221631-9	221631	Alexander Gramolin	02/2011
2283	10^221628+7	221629	Alfred Reich	04/2021
2284	2^735970-1839821	221550	Enzo Doria	06/2015
2285	2^735367+60293	221368	Enzo Doria	03/2016
2286	77*10^221343+3	221345	Robert Price	11/2023
2287	299^299^299-582	221328	Henri Lifchitz	03/2025
2288	(241^92821-1)/240	221099	Anonymous	04/2024
2289	(202*10^221092-1)/3	221094	Robert Price	06/2023
2290	(5^316297-1)/220142716	221074	Paul Vanderveen	05/2025
2291	(29^151153+1)/30	221045	Paul Bourdelais	09/2017
2292	2^734228+24751	221025	Enzo Doria	10/2023
2293	(28*10^220800+173)/3	220801	Robert Price	07/2024
2294	2^733264-2784089	220735	Enzo Doria	10/2015
2295	2^733114-24555	220690	Enzo Doria	09/2013
2296	2^731891-636259	220322	Enzo Doria	12/2013
2297	98*10^220185-9	220187	Robert Price	05/2023
2298	418319^39164+418318	220161	Alfred Reich	11/2023
2299	2^4^182829+182829^4^2	220149	Henri Lifchitz	03/2025
2300	2^731124-25539	220091	Enzo Doria	09/2013
2301	2^730972-462029	220045	Enzo Doria	07/2015
2302	2^730833+1868627	220003	Enzo Doria	04/2016
2303	2^730645-2787133	219947	Enzo Doria	11/2015
2304	2^730547-25581	219917	Enzo Doria	09/2013
2305	(113*13^197420-5)/12	219916	Anonymous	11/2022
2306	(13^197420*113-5)/12	219916	Eric Chen	10/2023
2307	2^730460+82291	219891	Enzo Doria	09/2016
2308	(5*10^219847-101)/3	219848	Robert Price	08/2023
2309	(2^730339+1)/(3278390620037943469324347)	219831	Gord Palameta	12/2018
2310	L(1051849)	219824	Renaud Lifchitz	03/2009
2311	3*2^730149+5	219798	Jon Grantham	07/2023
2312	8*10^219740-3	219741	Serge Batalov	01/2023
2313	11^210961-240	219694	Enzo Doria	01/2013
2314	(26*10^219639-77)/3	219640	Robert Price	03/2023
2315	2^729611-113437	219635	Enzo Doria	08/2014
2316	7^259710-2	219481	Paul Bourdelais	01/2021
2317	F(1049897)	219416	Henri Lifchitz	10/2008
2318	(1488^69151-1)/1487	219386	Alexander Zhirkov	02/2023
2319	2^728604+1879321	219332	Enzo Doria	10/2016
2320	33^144412+2	219292	Robert Price	04/2015
2321	2^728277-183313	219234	Hans Havermann	10/2018
2322	2^727998-1862711	219150	Enzo Doria	12/2015
2323	(29*10^219124+91)/3	219125	Robert Price	12/2022
2324	2^727729-114073	219069	Enzo Doria	12/2014
2325	2^727496-1851809	218999	Enzo Doria	08/2015
2326	2^727025+25907	218857	Enzo Doria	12/2023
2327	2^726591+2793143	218726	Enzo Doria	02/2016
2328	(7*10^218644+17)/3	218645	Robert Price	06/2023
2329	2^725534-2791931	218408	Enzo Doria	02/2016
2330	Phi(220531,10)/2686456812680882641	217774	Makoto Kamada	10/2020
2331	2^722184+1877821	217400	Enzo Doria	08/2016
2332	(109*10^217360-1)/9	217362	Serge Batalov	12/2014
2333	2^721721-4453	217260	Yves Minet	03/2021
2334	10^216950+49	216951	Robert Price	02/2023
2335	281*499979#/46410-2702372	216849	Robert Smith	08/2016
2336	281*499979#/46410+2400766	216849	Robert Smith	08/2016
2337	Phi(83733,-13#)	216643	Henri Lifchitz	02/2026
2338	tau(311^15786)	216429	Nik Lygeros / Olivier Rozier / LR team	10/2013
2339	2^718756-114107	216368	Enzo Doria	12/2014
2340	2^717672+121	216041	Stefano Morozzi	05/2021
2341	2^717305+80327	215931	Enzo Doria	07/2016
2342	Phi(358640,2^5)	215875	Henri Lifchitz	12/2025
2343	2^717069-59773	215860	Enzo Doria	10/2015
2344	10^215802+33	215803	Robert Price	08/2023
2345	30^146021-29^146021	215691	Jean-Louis Charton	09/2018
2346	277^88301-276^88301	215674	Jean-Louis Charton	06/2012
2347	2^716428+215011	215667	Enzo Doria	11/2023
2348	(13*10^215592-43)/3	215593	Robert Price	08/2023
2349	p(41292)#+p(41292+1)	215450	Henri Lifchitz	11/2024
2350	(29^147319-1)/466757843690852	215425	Paul Vanderveen	06/2025
2351	227^91413-40	215372	Enzo Doria	04/2015
2352	(2^715008-21)/5	215239	Stefano Morozzi	08/2022
2353	2^714717+782897	215152	Enzo Doria	11/2016
2354	(19^168013-1)/80910356454	214837	Paul Vanderveen	05/2025
2355	tau(373^15186)	214796	Nik Lygeros / Olivier Rozier / LR team	10/2013
2356	2^713241+1879157	214707	Enzo Doria	08/2016
2357	(23*10^214633+91)/3	214634	Robert Price	03/2023
2358	11^206081-10^206081	214612	Jean-Louis Charton	10/2011
2359	2^712801-69553	214575	Enzo Doria	01/2016
2360	2^712603-25357	214515	Enzo Doria	09/2013
2361	2^711721-1846723	214250	Enzo Doria	07/2015
2362	999^71336+998	213978	Alfred Reich	04/2026
2363	2^710730-396765	213952	Enzo Doria	09/2013
2364	(19*10^213934-37)/9	213935	Alfred Reich	12/2023
2365	(19*10^213730-37)/9	213731	Alfred Reich	12/2023
2366	(713^74897-1)/712	213685	Jinyuan Wang	08/2023
2367	2^709773+25907	213663	Enzo Doria	12/2023
2368	2^708468-114329	213271	Enzo Doria	02/2015
2369	2^708293+27557	213218	Enzo Doria	01/2024
2370	379*10^213199+9	213202	Jason Yuen	01/2025
2371	2^707277+28997	212912	Enzo Doria	02/2024
2372	(163*10^212779-1)/9	212781	Serge Batalov	12/2014
2373	2^706838-69041	212780	Enzo Doria	11/2015
2374	2^705653+25907	212423	Enzo Doria	12/2023
2375	22*10^212339+7	212341	Robert Price	10/2022
2376	2^704577-113871	212099	Enzo Doria	10/2014
2377	(2^704548-19)/3	212090	Stefano Morozzi	08/2022
2378	2^704110-2792441	211959	Enzo Doria	02/2016
2379	2^704084+28531	211951	Enzo Doria	02/2024
2380	2^703943-1862947	211908	Enzo Doria	12/2015
2381	(60^119083+1)/61	211746	Paul Bourdelais	10/2018
2382	163^95704-162	211716	Norbert Schneider	02/2026
2383	(184*10^211682-1)/3	211684	Robert Price	12/2022
2384	(10^211610-91)/9	211610	Serge Batalov	12/2014
2385	227^89797+2	211565	Lelio R Paula	08/2012
2386	2^702194-3	211382	Paul Bourdelais	03/2012
2387	2^702064+1874911	211343	Enzo Doria	07/2016
2388	2^701968-113873	211314	Enzo Doria	10/2014
2389	(14*10^211262-41)/9	211263	Serge Batalov	01/2023
2390	2^701713-113779	211237	Enzo Doria	09/2014
2391	2^701616-216803	211208	Enzo Doria	01/2024
2392	2^701449-25201	211158	Enzo Doria	09/2013
2393	2^701403-2786977	211144	Enzo Doria	11/2015
2394	2^701189-25423	211079	Enzo Doria	09/2013
2395	2^701162-459161	211071	Enzo Doria	05/2015
2396	2^700793+219407	210960	Enzo Doria	03/2024
2397	(24^152783-1)/23	210872	Paul Bourdelais	04/2018
2398	2^700400+9385	210842	Lelio R Paula	01/2014
2399	2^700304-17	210813	Stefano Morozzi	07/2022
2400	2^700131+1874693	210761	Enzo Doria	06/2016
2401	(2^700095+225414)/2	210750	Stefano Morozzi	04/2020
2402	(2^700090+278254)/2	210748	Stefano Morozzi	04/2020
2403	(2^700075+303666)/2	210744	Stefano Morozzi	04/2020
2404	(2^700073+75882)/2	210743	Stefano Morozzi	04/2020
2405	(2^700074+328890)/2	210743	Stefano Morozzi	04/2020
2406	(2^700052+79162)/2	210737	Stefano Morozzi	04/2020
2407	(2^700052+304458)/2	210737	Stefano Morozzi	04/2020
2408	(2^700048+376578)/2	210736	Stefano Morozzi	04/2020
2409	11^202357-1140	210734	Enzo Doria	12/2012
2410	(2^700021+25874)/2	210728	Stefano Morozzi	04/2020
2411	(2^700018+377518)/2	210727	Stefano Morozzi	04/2020
2412	2^699999+300729	210721	Norman Luhn	09/2023
2413	(238*10^210712-1)/3	210714	Robert Price	09/2023
2414	2^699740+25	210643	Stefano Morozzi	05/2021
2415	(23*10^210525-143)/3	210526	Robert Price	12/2023
2416	2^698929-2788423	210399	Enzo Doria	11/2015
2417	(5^300893+4^300893)/9	210315	Jean-Louis Charton	11/2011
2418	2^698316+1878601	210215	Enzo Doria	08/2016
2419	34*10^210097-9	210099	Robert Price	05/2023
2420	(19*10^210011-49)/3	210012	Robert Price	06/2023
2421	6*10^209846-91	209847	Robert Price	05/2023
2422	2^697036+1878751	209829	Enzo Doria	08/2016
2423	2^696813+28607	209762	Enzo Doria	02/2024
2424	(238*10^209715-1)/3	209717	Robert Price	09/2023
2425	6^269407+5	209640	Paul Bourdelais	02/2021
2426	(2^696343-1)/11141489/36009913139329	209600	Tony Prest / Never Odd Or Even	02/2014
2427	2^696254-115151	209594	Enzo Doria	06/2015
2428	2^695841+225	209470	Henri Lifchitz	01/2025
2429	(35^135623+1)/36	209410	Paul Bourdelais	07/2018
2430	7*10^209161+39	209162	Robert Price	01/2023
2431	2^694633+1887257	209106	Enzo Doria	05/2017
2432	fibonacci(999790)-4	208944	Jon Grantham	08/2023
2433	2^693959+180923	208903	Enzo Doria	07/2016
2434	(2^693747-11)/3	208839	Stefano Morozzi	08/2022
2435	2^693462-1847561	208753	Enzo Doria	07/2015
2436	2^690890-59981	207979	Enzo Doria	11/2015
2437	(38^131591+1)/39	207884	Paul Bourdelais	07/2018
2438	3*2^690484+5	207857	Jon Grantham	07/2023
2439	2^690163+1877063	207760	Enzo Doria	07/2016
2440	Phi(64773,-64773)	207680	Henri Lifchitz	06/2025
2441	7^245608-2	207563	Paul Bourdelais	01/2021
2442	(67*10^207556+23)/9	207557	Serge Batalov	01/2023
2443	2^689286-29381	207496	Enzo Doria	08/2015
2444	2^689122-114521	207447	Enzo Doria	04/2015
2445	9*10^207254-89	207255	Robert Price	02/2023
2446	2^688373+6077	207221	Enzo Doria	02/2016
2447	2^688201+1875527	207170	Enzo Doria	07/2016
2448	(42^127609+1)/43	207140	Paul Bourdelais	07/2018
2449	2^687938+213589	207090	Enzo Doria	10/2023
2450	2^687619+81563	206994	Enzo Doria	08/2016
2451	3*10^206927+37	206928	Robert Price	08/2023
2452	2^687383+21803	206923	Enzo Doria	09/2023
2453	(11*10^206688+19)/3	206689	Robert Price	07/2024
2454	2^686572-1845299	206679	Enzo Doria	07/2015
2455	(21^156217-1)/20	206552	Paul Bourdelais	04/2010
2456	2^685970+39415	206498	Enzo Doria	11/2024
2457	(2^685739+1)/(3*87774593)	206420	Gord Palameta	08/2018
2458	2^685578+3	206380	Paul Bourdelais	04/2012
2459	2^685078+218599	206230	Enzo Doria	01/2024
2460	2^684836-49349	206157	Enzo Doria	10/2015
2461	(73^110603-1)/72	206088	Paul Bourdelais	06/2018
2462	2^684163-2790967	205954	Enzo Doria	12/2015
2463	326^81943-325^81943	205941	Jean-Louis Charton	07/2012
2464	(2^684127-1)/23765203727	205933	Jens K. Andersen	04/2009
2465	(68*10^205510+13)/9	205511	Serge Batalov	01/2023
2466	4^341233-3^341233	205443	Jean-Louis Charton	01/2006
2467	2^682414+215029	205428	Enzo Doria	11/2023
2468	(963^68821-1)/962	205334	Jinyuan Wang	01/2024
2469	(43*10^205183-421)/9	205184	Robert Price	10/2023
2470	2^681545+467	205166	Lelio R Paula	11/2013
2471	2^681306+81049	205094	Enzo Doria	07/2016
2472	2^680697+1877057	204911	Enzo Doria	07/2016
2473	2^680415+71783	204826	Enzo Doria	04/2016
2474	10^204764-8001	204764	Robert Price	03/2023
2475	(26*10^204730-77)/3	204731	Robert Price	03/2023
2476	2^679860-459995	204659	Enzo Doria	06/2015
2477	2^679593+1879547	204578	Enzo Doria	09/2016
2478	2^678899+220073	204369	Enzo Doria	03/2024
2479	2^678753+21677	204326	Enzo Doria	08/2023
2480	2^678651+1875023	204295	Enzo Doria	07/2016
2481	2^678561+678561	204268	Henri Lifchitz	05/2006
2482	5*3^427884+2^427884	204154	Jon Grantham	08/2023
2483	2^678101-114043	204129	Enzo Doria	11/2014
2484	2^678028+1875631	204107	Enzo Doria	06/2016
2485	2^677721+28607	204015	Enzo Doria	01/2024
2486	(19*10^203798-7)/3	203799	Robert Price	12/2023
2487	2^676992-59783	203795	Enzo Doria	10/2015
2488	2^676972+1866871	203789	Enzo Doria	03/2016
2489	2^676815+22583	203742	Enzo Doria	09/2023
2490	2^676761-9	203726	Robert Price	01/2017
2491	2^676592-23	203675	Stefano Morozzi	07/2022
2492	2^676563-2792407	203666	Enzo Doria	02/2016
2493	2^676306-114713	203589	Enzo Doria	04/2015
2494	(2^675977-1)/(1686378749257*7171117283326998925471)	203456	Dario Alpern	07/2015
2495	6*10^203365+53	203366	Robert Price	09/2023
2496	2^675433-118231	203326	Stefano Morozzi	09/2025
2497	2^675433-138811	203326	Stefano Morozzi	09/2025
2498	2^675430-133685	203325	Stefano Morozzi	09/2025
2499	2^675430-29937	203325	Stefano Morozzi	09/2025
2500	2^675430-57281	203325	Stefano Morozzi	09/2025

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