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.

A047511 Numbers that are congruent to {0, 2, 4, 6, 7} mod 8.

Original entry on oeis.org

0, 2, 4, 6, 7, 8, 10, 12, 14, 15, 16, 18, 20, 22, 23, 24, 26, 28, 30, 31, 32, 34, 36, 38, 39, 40, 42, 44, 46, 47, 48, 50, 52, 54, 55, 56, 58, 60, 62, 63, 64, 66, 68, 70, 71, 72, 74, 76, 78, 79, 80, 82, 84, 86, 87, 88, 90, 92, 94, 95, 96, 98, 100, 102, 103
Offset: 1

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Keywords

Programs

  • Magma
    [n : n in [0..150] | n mod 8 in [0, 2, 4, 6, 7]]; // Wesley Ivan Hurt, Jul 31 2016
  • Maple
    A047511:=n->8*floor(n/5)+[(0, 2, 4, 6, 7)][(n mod 5)+1]: seq(A047511(n), n=0..100); # Wesley Ivan Hurt, Jul 31 2016
  • Mathematica
    Select[Range[0,100], MemberQ[{0,2,4,6,7}, Mod[#,8]]&] (* or *) LinearRecurrence[ {1,0,0,0,1,-1}, {0,2,4,6,7,8}, 100] (* Harvey P. Dale, May 09 2014 *)

Formula

a(0)=0, a(1)=2, a(2)=4, a(3)=6, a(4)=7, a(5)=8, a(n) = a(n-1) + a(n-5) - a(n-6) for n > 6. - Harvey P. Dale, May 09 2014
From Wesley Ivan Hurt, Jul 31 2016: (Start)
G.f.: x^2*(2+2*x+2*x^2+x^3+x^4)/((x-1)^2*(1+x+x^2+x^3+x^4)).
a(n) = a(n-5) + 8 for n > 5.
a(n) = (40*n - 25 + 3*(n mod 5) - 2*((n+1) mod 5) - 2*((n+2) mod 5) - 2*((n+3) mod 5) + 3*((n+4) mod 5))/25.
a(5k) = 8k-1, a(5k-1) = 8k-2, a(5k-2) = 8k-4, a(5k-3) = 8k-6, a(5k-4) = 8k-8. (End)