1169832domain: NAppears in sequencesa(n) = Sum_{k=1..n} C(n-1,k-1) * S2(n,k) for n>0, a(0)=1, where S2(n,k) = A048993(n,k) are Stirling numbers of the 2nd kind.at n=9A134055Triangle read by rows, T(n, k) = Sum_{j=0..n} (-1)^(n-j)*C(-j, -n)*S2(k, j), S2 the Stirling set numbers A048993, for n >= 0 and 0 <= k <= n.at n=54A271701