a(n) = n*(n-1)*(n-2)(27*n^3 - 174*n^2 + 511*n - 552)*n!/48.
A138784
a(n) = n*(n-1)*(n-2)(27*n^3 - 174*n^2 + 511*n - 552)*n!/48.
Terms
- a(0) =0a(1) =0a(2) =108a(3) =5232a(4) =154200a(5) =3747600a(6) =82908000a(7) =1756661760a(8) =36715472640a(9) =770648256000
External references
- oeis: A138784