116636domain: NAppears in sequencesa(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = (F(2), F(3), F(4), ... ).at n=19A024861Number of length 4 1..(n+1) arrays with every leading partial sum divisible by 2, 3, 5, 7 or 11.at n=22A254951