a(n) = n! * 2^n * Sum_{i=1..n} 1/(i*2^i).

A068102

a(n) = n! * 2^n * Sum_{i=1..n} 1/(i*2^i).

Terms

    a(0) =1a(1) =5a(2) =32a(3) =262a(4) =2644a(5) =31848a(6) =446592a(7) =7150512a(8) =128749536a(9) =2575353600a(10) =56661408000

External references