3,2

Semiprime analogue of A033933. After n = 3, a(n) is never again 0.

a(n) = MIN{k such that n!-k is in A001358 and k>=0}.

a(3) = 0 because 3! - 0 = 6 - 0 = 6 = 2 * 3.

a(4) = 2 because 4! - 2 = 24 - 2 = 22 = 2 * 11.

a(5) = 1 because 5! - 1 = 119 = 7 * 17.

Cf. A001358, A033933.

Sequence in context: A000139 A114572 A052621 this_sequence A051852 A054495 A007966

Adjacent sequences: A131054 A131055 A131056 this_sequence A131058 A131059 A131060

easy,nonn

Jonathan Vos Post (jvospost3(AT)gmail.com), Sep 24 2007