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.

A132736 Row sums of triangle A132735.

Original entry on oeis.org

1, 2, 5, 10, 19, 36, 69, 134, 263, 520, 1033, 2058, 4107, 8204, 16397, 32782, 65551, 131088, 262161, 524306, 1048595, 2097172, 4194325, 8388630, 16777239, 33554456, 67108889, 134217754, 268435483, 536870940, 1073741853, 2147483678
Offset: 0

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Author

Gary W. Adamson, Aug 26 2007

Keywords

Comments

Apart from first term, the same as A052944. - R. J. Mathar, Jun 12 2008

Examples

			a(4) = 19 = sum of row 4 terms of triangle A132735: (1 + 5 + 7 + 5 + 1).
a(3) = 10 = (1, 3, 3, 1) dot (1, 1, 2, 0) = (1 + 3 + 6 + 0).
		

Crossrefs

Cf. A132735.

Programs

  • Magma
    [1] cat [2^n + n-1: n in [1..30]]; // G. C. Greubel, Feb 14 2021
  • Maple
    a:= proc(n) option remember; if n=0 then 1 else add((binomial(n,j)+1), j=0..n-1) fi end: seq(a(n), n=0..31);# Zerinvary Lajos, Mar 29 2009
  • Mathematica
    Table[2^n + n-1 + Boole[n==0], {n,0,30}] (* G. C. Greubel, Feb 14 2021 *)
  • Sage
    [1]+[2^n + n-1 for n in (1..30)] # G. C. Greubel, Feb 14 2021
    

Formula

Binomial transform of [1, 1, 2, 0, 2, 0, 2, 0, 2, ...].
From Colin Barker, Aug 12 2012: (Start)
a(n) = 4*a(n-1) -5*a(n-2) +2*a(n-3) for n>3.
G.f.: (1 -2*x +2*x^2 -2*x^3)/((1-x)^2*(1-2*x)). (End)
From G. C. Greubel, Feb 14 2021: (Start)
a(n) = 2^n + n - 1 + [n=0].
E.g.f.: 1 - (1-x)*exp(x) + exp(2*x). (End)

Extensions

More terms from R. J. Mathar, Jun 12 2008