a(n) equals the sum of all permutations of compositions of functions (1 + k*x) for k=1..n, evaluated at x=1.

A277406

a(n) equals the sum of all permutations of compositions of functions (1 + k*x) for k=1..n, evaluated at x=1.

Terms

    a(0) =1a(1) =2a(2) =9a(3) =76a(4) =1100a(5) =25176a(6) =846132a(7) =39321696a(8) =2413753344a(9) =189030205440

External references