2298744

Appears in sequences

• Number of functions f:{1,2,...,n}->{1,2,...,n} such that Im(f) contains 4 fixed elements.at n=4A126780
• Triangular array T(n,k): functions f:{1,2,...,n}-> {1,2,...,n} such that each of k fixed (but arbitrary) elements are in the image of f.at n=40A174551
• Triangle read by rows: T(n,k) = Sum_{j=0..k} (-1)^(k-j) * binomial(k,j) * (4+j)^n.at n=40A391633