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.

A116521 Binomial transform of tetranacci sequence A000078.

Original entry on oeis.org

0, 0, 0, 1, 5, 17, 51, 148, 429, 1250, 3655, 10701, 31336, 91752, 268623, 786414, 2302262, 6739984, 19731685, 57765711, 169112717, 495088023, 1449400960, 4243211207, 12422263776, 36366946961, 106466490879, 311687250156
Offset: 0

Views

Author

Jonathan Vos Post, Mar 10 2006

Keywords

Comments

See also A115390, the binomial transform of tribonacci sequence A000073. Tetranacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) + a(n-4), with a(0) = a(1) = a(2) = 0, a(3) = 1.

Examples

			Table shows the tetranacci numbers multiplied into rows of Pascal's triangle.
1*0 = 0.
1*0 + 1*0 = 0.
1*0 + 2*0 + 1*0 = 0.
1*0 + 3*0 + 3*0 + 1* 1 = 1.
1*0 + 4*0 + 6*0 + 4*1 + 1*1 = 5.
1*0 + 5*0 + 10*0 + 10*1 + 5*1 + 1*2 = 17.
		

Crossrefs

Programs

  • Maple
    t[0]:=0: t[1]:=0: t[2]:=0: t[3]:=1: for n from 4 to 35 do t[n]:=t[n-1]+t[n-2]+t[n-3]+t[n-4] od: seq(add(binomial(n,k)*t[k],k=0..n),n=0..30); # end of first Maple program
    G:=x^3/(1-5*x+8*x^2-6*x^3+x^4): Gser:=series(G,x=0,33): seq(coeff(Gser,x,n),n=0..30); # Emeric Deutsch, Apr 09 2006
  • Mathematica
    LinearRecurrence[{5,-8,6,-1}, {0,0,0,1}, 25] (* G. C. Greubel, Nov 03 2016 *)
  • PARI
    a(n)=([0,1,0,0; 0,0,1,0; 0,0,0,1; -1,6,-8,5]^n*[0;0;0;1])[1,1] \\ Charles R Greathouse IV, Jun 28 2017

Formula

a(n) = Sum_{k=0..n} C(n,k) * A000078(k).
G.f.: x^3/(1-5*x+8*x^2-6*x^3+x^4). - Emeric Deutsch, Apr 09 2006
a(n) = 5*a(n-1) - 8*a(n-2) + 6*a(n-3) - a(n-4). - G. C. Greubel, Nov 03 2016

Extensions

Definition corrected by Franklin T. Adams-Watters, Mar 13 2006
More terms from Emeric Deutsch, Apr 09 2006