A144796 Expansion of x(5+215x-1253x^2-23x^3)/((1+34x+x^2)(1-34x+x^2)).

5, 215, 4517, 248087, 5212613, 286292183, 6015350885, 330380931095, 6941709708677, 381259308191447, 8010726988462373, 439972911271998743, 9244372002975869765, 507728358348578357975, 10667997280707165246437

Offset: 1

Author

Richard Choulet, Sep 21 2008

Keywords

• nonn
• easy

Comments

The original definition "Numbers n such that (n^2-17)/2 is a square" describes A077242. - R. J. Mathar, Nov 27 2011

Links

• Index entries for linear recurrences with constant coefficients, signature (0,1154,0,-1).

Programs

Mathematica

Rest[CoefficientList[Series[x (5+215x-1253x^2-23x^3)/((1+34x+x^2)(1-34x+x^2)),{x,0,30}],x]] (* or *) LinearRecurrence[{0,1154,0,-1},{5,215,4517,248087},30] (* Harvey P. Dale, Apr 04 2014 *)

PARI

Vec(x(5+215*x-1253*x^2-23*x^3)/((1+34*x+x^2)*(1-34*x+x^2))+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012

Formula

a(n) = 1154*a(n-2) - a(n-4).