174805

Appears in sequences

• Triangle of numbers a(n,k), 0 <= k <= n: number of set partitions of {1,2,...,n} in which exactly k of the blocks have been distinguished.at n=48A049020
• Triangle of sums of Jacobsthal numbers related to binomial(4n,n)/(3n+1) mod 4.at n=39A113049
• Triangle read by rows: T(n,k) = Sum_{j=k..n} binomial(n,j)*Stirling_2(j,k)*Bell(n-j), where Bell(n) = A000110(n), for n >= 1, 0 <= k <= n-1.at n=39A244489
• E.g.f.: exp(exp(x) - 1) * (exp(x) - 1)^3 / 3!.at n=6A346842
• Expansion of (1/x) * Series_Reversion( x * (1 - x)^2 * (1 - x^3 / (1 - x)^3) ).at n=8A389630