a(n) = n! * (1 + Sum_{k=0..n} (-1)^k * binomial(k+2,3) / k!).
A368767
a(n) = n! * (1 + Sum_{k=0..n} (-1)^k * binomial(k+2,3) / k!).
Terms
- a(0) =1a(1) =0a(2) =4a(3) =2a(4) =28a(5) =105a(6) =686a(7) =4718a(8) =37864a(9) =340611a(10) =3406330a(11) =37469344a(12) =449632492a(13) =5845221941a(14) =81833107734
External references
- oeis: A368767