A256511 a(n) = (n^2 - 1)!.

1, 6, 40320, 1307674368000, 620448401733239439360000, 10333147966386144929666651337523200000000, 12413915592536072670862289047373375038521486354677760000000000

Offset: 1

Author

Nichole Suomi Smith, Mar 31 2015

Keywords

• nonn

Crossrefs

Cf. A000142, A000290, A088020.

Programs

Maple

seq(factorial(i^2-1), i = 1 .. 8);

Mathematica

(Range[10]^2-1)! (* Harvey P. Dale, Oct 07 2023 *)

Formula

a(n) = (2*Pi)^(1/2 - n/2)*n^(n^2 - 1/2)*Product_{j=0..n-1} Gamma(n+j/n). - Karol A. Penson, Jan 11 2024