A119700 a(n) = n*binomial(2*n, n)*Fibonacci(n)^2.

0, 2, 12, 240, 2520, 31500, 354816, 4060056, 45405360, 505842480, 5588869000, 61464995592, 672880545792, 7340296254200, 79824251379600, 865788437880000, 9368862119134560, 101178055201047660, 1090713358902182400, 11739380070425284200, 126171548138325690000

Offset

0,2

Links

Table of n, a(n) for n=0..20.

Formula

Sum_{n>=0} a(n)/16^n = (10 + 5*sqrt(325 + 10*sqrt(5)))/(125*sqrt(5)). - Amiram Eldar, May 05 2023

Maple

[seq(fib(n)^2*n*binomial(2*n, n), n=0..25)];

Mathematica

a[n_] := n * Binomial[2 n, n] * Fibonacci[n]^2; Array[a, 25, 0] (* Amiram Eldar, May 05 2023 *)

Crossrefs

Cf. A000045, A000984.

Sequence in context: A011840 A296462 A125804 * A141083 A257665 A132877

Adjacent sequences: A119697 A119698 A119699 * A119701 A119702 A119703

Keyword

nonn,easy

Author

Zerinvary Lajos, Jun 09 2006

Status

approved