A014772 Squares of even hexagonal numbers.

36, 784, 4356, 14400, 36100, 76176, 142884, 246016, 396900, 608400, 894916, 1272384, 1758276, 2371600, 3132900, 4064256, 5189284, 6533136, 8122500, 9985600, 12152196, 14653584, 17522596, 20793600, 24502500, 28686736

Offset

1,1

Links

Table of n, a(n) for n=1..26.

Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).

Formula

G.f.: 4*x*(9+151*x+199*x^2+25*x^3)/(1-x)^5. - Maksym Voznyy (voznyy(AT)mail.ru), Aug 11 2009

a(1)=36, a(2)=784, a(3)=4356, a(4)=14400, a(5)=36100, a(n) = 5*a(n-1)-10*a(n-2)+10*a(n-3)-5*a(n-4)+a(n-5). - Harvey P. Dale, May 11 2012

Mathematica

Take[Table[n(2n-1), {n, 60}], {2, -1, 2}]^2 (* Harvey P. Dale, May 11 2012 *)
(* Alternative: *)
LinearRecurrence[ {5, -10, 10, -5, 1}, {36, 784, 4356, 14400, 36100}, 30] (* Harvey P. Dale, May 11 2012 *)

Crossrefs

Cf. A014635.

Sequence in context: A280123 A004338 A228331 * A110206 A133051 A215605

Adjacent sequences: A014769 A014770 A014771 * A014773 A014774 A014775

Keyword

nonn,easy,changed

Author

Mohammad K. Azarian

Extensions

G.f. proposed by Maksym Voznyy checked and corrected by R. J. Mathar, Sep 16 2009

More terms from Erich Friedman

Status

approved