87178286161domain: NAppears in sequencesPrimes of the form (2*k)! - k! + 1.at n=2A118812Least prime factor of (2n)! - n! + 1 (= A237580(n)).at n=6A237579a(n) = (2n)! - n! + 1.at n=7A237580a(n) = Sum_{d|n} (-1)^(n/d+1)*d!.at n=13A321521