A010053 a(n) = 4^n*(2*n+1)!*(n!)^2/(n+1).

1, 12, 2560, 2903040, 10701766656, 98099527680000, 1888892391260160000, 68028459471234662400000, 4210629057689788455321600000, 419914246162041071241548267520000, 64132357595657181789618280857600000000, 14397414995889590911587619167220531200000000

Offset

0,2

Links

Andrew Howroyd, Table of n, a(n) for n = 0..100

Maple

4^n*(2*n+1)!*(n!)^2/(n+1);

Mathematica

Table[(4^n (2n+1)! (n!)^2)/(n+1), {n, 0, 10}] (* Harvey P. Dale, Nov 04 2017 *)

Prog

(PARI) a(n) = {4^n*(2*n+1)!*(n!)^2/(n+1)} \\ Andrew Howroyd, Jan 01 2020

Crossrefs

Sequence in context: A228289 A306391 A195536 * A092299 A006272 A111237

Adjacent sequences: A010050 A010051 A010052 * A010054 A010055 A010056

Keyword

nonn,easy

Author

Joe Keane (jgk(AT)jgk.org)

Extensions

Terms a(10) and beyond from Andrew Howroyd, Jan 01 2020

Status

approved