44316domain: NAppears in sequencesNumber of subsets of {1, ..., n} that are sum-free but not double-free.at n=24A088811Triangle read by rows based on the Stirling numbers S1: t(n,m)=Sum[(-1)^(n + 1)* StirlingS1[n, j]*(k + 1 - j)^(n - 1), {j, 0, k + 1}].at n=16A152918