A factorial prime is a prime number of the form n! ± 1, where n! is a factorial. n! - 1 is prime for n = 3, 4, 6, 7, 12, 14, 30, 32, 33, 38, 94, 166, 324, 379, 469, 546, 974, 1963, 3507, 3610, 6917, 21480, 26951, 34790, 94550, 103040, 147855, 208003, ... (OEIS A002982), the largest of which are summarized in the following table. n! - 1 | digits | discoverer 26951! - 1 | 107, 707 | Marchal, Carmody, and Kuosa (Caldwell; May 2002) 34790! - 1 | 142, 891 | Marchal, Carmody, and Kuosa (Caldwell; May 2002) 94550 - !1 | 429, 390 | D. Domanov/PrimeGrid (Oct. 4, 2010) 103040! - 1 | 471, 794 | J. Winskill/PrimeGrid (Dec. 14, 2010) 147855! - 1 | 700, 177 | PrimeGrid (Aug. 30, 2013) 208003! - 1 | 1, 015, 843 | S. Fukui (Jul. 25, 2016; http://primes.utm.edu/primes/page.php?id=121944)

double factorial prime | factorial | integer sequence primes | prime number | primorial prime