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.

A228843 a(n) = 4^n*A228842(n).

Original entry on oeis.org

2, 24, 448, 9216, 192512, 4030464, 84410368, 1767899136, 37027315712, 775510032384, 16242492571648, 340187179646976, 7124972786941952, 149227367389200384, 3125458558976524288, 65460453902527758336, 1371021545886168645632, 28715048051506270961664
Offset: 0

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Author

R. J. Mathar, Nov 10 2013

Keywords

Comments

Bhadouria et al. call this the 4-binomial transform of the 4-Lucas sequence.
Binomial transform of the binomial transform of the binomial transform of A087215.

Programs

  • Mathematica
    LinearRecurrence[{24,-64},{2,24},20] (* Harvey P. Dale, Jul 04 2022 *)
  • PARI
    Vec(2*(1 - 12*x) / (1 - 24*x + 64*x^2 ) + O(x^30)) \\ Colin Barker, Sep 23 2017

Formula

G.f.: 2*( 1-12*x ) / ( 1-24*x+64*x^2 ).
a(n) = 2*A098647(n).
a(n) = A000302(n)*A228842(n). - Omar E. Pol, Nov 10 2013
From Colin Barker, Sep 23 2017: (Start)
a(n) = 24*a(n-1) - 64*a(n-2) for n>1.
a(n) = (12-4*sqrt(5))^n + (4*(3+sqrt(5)))^n.
(End)