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.

A260160 a(n) = a(n-2) + a(n-6) - a(n-8) with n>8, the first eight terms are 0 except that for a(5) = a(7) = 1.

Original entry on oeis.org

0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 2, 0, 2, 0, 2, 0, 3, 0, 3, 0, 3, 0, 4, 0, 4, 0, 4, 0, 5, 0, 5, 0, 5, 0, 6, 0, 6, 0, 6, 0, 7, 0, 7, 0, 7, 0, 8, 0, 8, 0, 8, 0, 9, 0, 9, 0, 9, 0, 10, 0, 10, 0, 10, 0, 11, 0, 11, 0, 11, 0, 12, 0, 12, 0, 12, 0, 13, 0, 13, 0, 13, 0, 14, 0, 14, 0, 14
Offset: 1

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Comments

Sequence related to A264041 (1 is the offset of A264041).

Crossrefs

Cf. A000004 (second bisection), A000217, A002264 (for the first bisection), A264041.

Programs

  • Maple
    with(numtheory): P:= proc(q) local n; for n from 0 to q do
    print((1-(-1)^n)*floor(n/6+1/3)/2); od; end: P(100); # Paolo P. Lava, Nov 12 2015
  • Mathematica
    LinearRecurrence[{0, 1, 0, 0, 0, 1, 0, -1}, {0, 0, 0, 0, 1, 0, 1, 0}, 100]
    Table[(1 - (-1)^n) (Floor[n/6 + 1/3]/2), {n, 1, 90}] (* Bruno Berselli, Nov 10 2015 *)
  • PARI
    concat(vector(4), Vec(x^5/(1-x^2-x^6+x^8) + O(x^100))) \\ Altug Alkan, Nov 10 2015
    
  • Sage
    [(1-(-1)^n)*floor(n/6+1/3)/2 for n in (1..90)] # Bruno Berselli, Nov 10 2015

Formula

G.f.: x^5/(1-x^2-x^6+x^8).
a(n) = A264041(n) - n*(n+1)/2, 026).
a(n) = (1-(-1)^n)*floor(n/6+1/3)/2. [Bruno Berselli, Nov 10 2015]