-9000domain: ZAppears in sequencesA symmetrical triangular sequence:t(n,m)=(StirlingS1[n, m] + StirlingS1[n, n - m])*Binomial[n, m] - (StirlingS1[n, 0] + StirlingS1[n, n - 0])* Binomial[n, 0] + 1.at n=24A174834G.f.: Sum_{n>=0} x^n * (1 + x^n)^n / (1 + x^(n+1))^(n+1).at n=67A323557