A017128 a(n) = (8*n + 5)^4.

625, 28561, 194481, 707281, 1874161, 4100625, 7890481, 13845841, 22667121, 35153041, 52200625, 74805201, 104060401, 141158161, 187388721, 244140625, 312900721, 395254161, 492884401, 607573201

Offset

0,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

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

Formula

a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5); a(0)=625, a(1)=28561, a(2)=194481, a(3)=707281, a(4)=1874161. - Harvey P. Dale, Dec 17 2013

G.f.: ( -625 - 25436*x - 57926*x^2 - 14236*x^3 - 81*x^4 ) / ( (x-1)^5 ). - R. J. Mathar, May 08 2015

Mathematica

(8*Range[0, 30]+5)^4 (* or *) LinearRecurrence[{5, -10, 10, -5, 1}, {625, 28561, 194481, 707281, 1874161}, 30] (* Harvey P. Dale, Dec 17 2013 *)

Prog

(Magma) [(8*n+5)^4: n in [0..35] ]; // Vincenzo Librandi, Jul 21 2011

Crossrefs

Sequence in context: A156162 A017044 A080175 * A180259 A017224 A106321

Adjacent sequences: A017125 A017126 A017127 * A017129 A017130 A017131

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved