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.

A028290 Expansion of 1/((1-x)(1-x^2)(1-x^3)(1-x^5)(1-x^8)).

Original entry on oeis.org

1, 1, 2, 3, 4, 6, 8, 10, 14, 17, 22, 27, 33, 40, 48, 57, 68, 79, 93, 107, 124, 142, 162, 184, 209, 235, 265, 296, 331, 368, 409, 452, 500, 550, 605, 663, 726, 792, 864, 939, 1021, 1106, 1198, 1294, 1397, 1505
Offset: 0

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Number of partitions of n into parts equal to 1, 2, 3, 5 and 8. E.g. a(5)=6 because we have 5, 3+2, 3+1+1, 2+2+1, 2+1+1+1 and 1+1+1+1+1. - Emeric Deutsch, Mar 25 2005

Crossrefs

Programs

  • Haskell
    import Data.MemoCombinators (memo2, integral)
    a028290 n = a028290_list !! n
    a028290_list = map (p' 0) [0..] where
       p' = memo2 integral integral p
       p _ 0 = 1
       p 5 _ = 0
       p k m | m < parts !! k = 0
             | otherwise = p' k (m - parts !! k) + p' (k + 1) m
       parts = [1, 2, 3, 5, 8]
    -- Reinhard Zumkeller, Dec 09 2015
  • Maple
    G:=1/(1-x)/(1-x^2)/(1-x^3)/(1-x^5)/(1-x^8): Gser:=series(G,x=0,47): 1, seq(coeff(Gser,x^n),n=1..45); # Emeric Deutsch, Mar 25 2005
  • Mathematica
    CoefficientList[ Series[ 1/Product[1 - x^Fibonacci[i], {i, 2, 6}], {x, 0, 45}], x] (* Robert G. Wilson v, Oct 15 2016 *)
    CoefficientList[Series[1/((1-x)(1-x^2)(1-x^3)(1-x^5)(1-x^8)),{x,0,100}],x] (* Harvey P. Dale, Jan 26 2019 *)
  • PARI
    Vec(1/((1-x)*(1-x^2)*(1-x^3)*(1-x^5)*(1-x^8))+O(x^99)) \\ Charles R Greathouse IV, Sep 27 2012