A152456 a(n)=1*(n+2)!-2*(n+1)!-3*n!.

-3, -1, 6, 54, 408, 3240, 28080, 267120, 2782080, 31570560, 388281600, 5149267200, 73287244800, 1114636723200, 18045906278400, 309918825216000, 5628230479872000, 107773290713088000, 2170404686241792000

Offset

0,1

Links

Table of n, a(n) for n=0..18.

Mathematica

a[n_]:=1*(n+2)!-2*(n+1)!-3*n!;

Crossrefs

Sequence in context: A221852 A363196 A025230 * A128605 A051511 A272030

Adjacent sequences: A152453 A152454 A152455 * A152457 A152458 A152459

Keyword

sign

Author

Vladimir Joseph Stephan Orlovsky, Dec 05 2008

Extensions

Offset changed from 1 to 0 by Georg Fischer, May 08 2021

Status

approved