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PrimeGrid Fermat Divisor Search
Fermat Divisor Search was a PrimeGrid project searching for large Fermat divisors. It began in September 2019, and ended in April 2021.[1]
Purpose
The project searched for Fermat divisors of the form k•2n+1, for the following ranges:[1]
- 5 ≤ k ≤ 49 for n ≤ 9,000,000, with two exceptions:
- k = 9 and 27 did not search even n-values, because they cannot produce Fermat divisors.[2]
- k = 1323, 2187, 3267 for even[3] n ≤ 3,322,000
- k = 3125, 3375 for n ≤ 3,322,000
- k = 19683 for n ≤ 4,000,000
Found primes
- 2021-03-01: 25•28788628+1
- 2021-02-17: 17•28636199+1
- 2021-01-27: 25•28456828+1
- 2021-01-23: 39•28413422+1
- 2021-01-19: 31•28348000+1
- 2021-01-14: 27•27963247+1, divides F(7963245)
- 2021-01-14: 39•27946769+1
- 2021-01-14: 29•27899985+1
- 2020-12-13: 45•27661004+1
- 2020-12-06: 15•27619838+1
- 2020-11-12: 45•27513661+1
- 2020-10-27: 29•27374577+1
- 2020-10-25: 15•27300254+1
- 2020-10-24: 19•26833086+1
- 2020-10-20: 39•26684941+1
- 2020-10-20: 39•26648997+1
- 2020-08-15: 39•26164630+1
- 2020-06-04: 21•26048861+1
- 2020-02-16: 41•25651731+1
- 2020-01-28: 31•25560820+1
- 2020-01-22: 13•25523860+1
- 2019-12-21: 45•25308037+1
- 2019-11-23: 39•25119458+1
- 2019-10-16: 15•24800315+1
- 2019-10-14: 31•24673544+1
- 2019-10-14: 39•24657951+1
- 2019-10-12: 29•24532463+1
- 2019-10-12: 25•24481024+1
- 2019-10-10: 23•24300741+1
- 2019-10-02: 37•24046360+1
- 2019-09-28: 29•23964697+1
- 2019-09-28: 39•23961129+1
- 2019-09-22: 49•23837090+1
- 2019-09-18: 25•23733144+1
- 2019-09-17: 45•23677787+1
- 2019-09-16: 33•23649810+1
- 2019-09-13: 3125•23124079+1
- 2019-09-11: 3125•22867399+1
- 2019-09-11: 2187•22786802+1
- 2019-09-11: 1323•22764024+1
- 2019-09-11: 3125•22697651+1
- 2019-09-09: 3375•22314297+1
- 2019-09-09: 3267•22305266+1
- 2019-09-09: 1323•22186806+1
- 2019-09-09: 1323•22205832+1
- 2019-09-09: 3267•22173170+1
- 2019-09-08: 3125•21583223+1
- 2019-09-08: 19683•22265896+1
- 2019-09-07: 19683•22033900+1
- 2019-09-07: 19683•21868828+1
- 2019-09-07: 19683•21797997+1
- 2019-09-07: 19683•2901745+1
- 2019-09-06: 19683•2493846+1
- 2019-09-06: 19683•2485845+1
- 2019-09-06: 19683•2366665+1