cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A097725 Chebyshev U(n,x) polynomial evaluated at x=51.

Original entry on oeis.org

1, 102, 10403, 1061004, 108212005, 11036563506, 1125621265607, 114802332528408, 11708712296632009, 1194173851923936510, 121794024183944892011, 12421796292910455048612, 1266901427852682470066413, 129211523844680701491725514, 13178308530729578869685936015
Offset: 0

Views

Author

Wolfdieter Lang, Aug 31 2004

Keywords

Comments

Used to form integer solutions of Pell equation a^2 - 26*b^2 =-1. See A097726 with A097727.

Programs

  • Mathematica
    ChebyshevU[Range[0,20],51] (* Harvey P. Dale, Oct 08 2012 *)
    LinearRecurrence[{102, -1},{1, 102},15] (* Ray Chandler, Aug 11 2015 *)

Formula

a(n) = 102*a(n-1) - a(n-2), n>=1, a(0)=1, a(-1):=0.
a(n) = S(n, 2*51)= U(n, 51), Chebyshev's polynomials of the second kind. See A049310.
G.f.: 1/(1-102*x+x^2).
a(n)= sum((-1)^k*binomial(n-k, k)*102^(n-2*k), k=0..floor(n/2)), n>=0.
a(n) = ((51+10*sqrt(26))^(n+1) - (51-10*sqrt(26))^(n+1))/(20*sqrt(26)).

Extensions

More terms from Harvey P. Dale, Oct 08 2012