A082034 a(n) = (4*n + 1)*n!.

1, 5, 18, 78, 408, 2520, 18000, 146160, 1330560, 13426560, 148780800, 1796256000, 23471078400, 330032102400, 4969162598400, 79768136448000, 1359981342720000, 24542432538624000, 467373280518144000, 9366672731480064000

Offset: 0

Author

Paul Barry, Apr 02 2003

Keywords

• nonn
• easy

Comments

A row of the array A082037.

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..400

Crossrefs

Cf. A082033, A007680.

Programs

Magma

[(4*n+1)*Factorial(n) : n in [0..20]]; // Vincenzo Librandi, Sep 22 2011

Mathematica

Table[(4n+1)n!,{n,0,20}] (* Harvey P. Dale, Mar 02 2022 *)

Formula

a(n) = A016813(n)*n!.

(-4*n+3)*a(n) + n*(4*n+1)*a(n-1) = 0. - R. J. Mathar, Nov 07 2014

4*a(n) + (-4*n-7)*a(n-1) + 3*(n-1)*a(n-2) = 0. - R. J. Mathar, Nov 07 2014