-316234143225domain: ZAppears in sequences2-adic factorial function.at n=23A055634a(n) = n!*b(n) where b(n) = (n-4)*b(n-2)/(n*(n-1)) and b(0) = b(1) = 1.at n=27A123022Q(2,n), where Q(m,k) is defined in A127080 and A127137.at n=23A127144