986400domain: NAppears in sequencesa(n) = n! * Sum_{k=0..n-2} 1/k!.at n=9A038154Multiply by 1, add 1, multiply by 2, add 2, etc., starting with 0.at n=17A082458Triangle read by rows: T(n,m) is the number of length n decorated permutations avoiding the word 0^m = 0...0 of m 0's, where 1 <= m <= n.at n=43A334156