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.

A191869 First differences of the dying rabbits sequence A000044.

Original entry on oeis.org

0, 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 88, 143, 231, 373, 603, 974, 1574, 2543, 4109, 6639, 10727, 17332, 28004, 45248, 73109, 118126, 190862, 308385, 498273, 805084, 1300814, 2101789, 3395964, 5487026, 8865658, 14324680, 23145090, 37396661, 60423625
Offset: 1

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Keywords

Crossrefs

Cf. A000044.

Programs

  • Mathematica
    A000044 = CoefficientList[Series[1/(1 - z - z^3 - z^5 - z^7 - z^9 - z^11), {z, 0, 200}], z]; GetDiff[seq_List] := Drop[seq, 1] - Drop[seq, -1]; A191869 = GetDiff[A000044]
  • PARI
    A191869_list=Vec((-x^11-x^9-x^7-x^5-x^3)/(x^11+x^9+x^7+x^5+x^3+x-1)+O(x^99)) /* returns a list of the first 96 nonzero terms, a(3)...a(99) */
    
  • PARI
    A191869(n)=polcoeff((1+x^2+x^4+x^6+x^8)/(1-x-x^3-x^5-x^7-x^9-x^11+O(x^max(1,n-2))),n-3)  \\ M. F. Hasler, Jun 19 2011

Formula

G.f.: x^3(1 + x + x^2 + x^3 + x^4)(1 - x + x^2 - x^3 + x^4)/(1 - x - x^3 - x^5 - x^7 - x^9 - x^11). - Charles R Greathouse IV, Jun 19 2011