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.

A234868 a(n) = 2*binomial(11*n+2,n)/(11*n+2).

Original entry on oeis.org

1, 2, 23, 374, 7095, 146916, 3219216, 73386170, 1722567143, 41352865400, 1010607195741, 25058477434562, 628845572227600, 15941429819185752, 407626109449551300, 10501154649486399096, 272294680440574235015, 7101160966497659412010, 186134223613500403098396
Offset: 0

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Author

Tim Fulford, Jan 01 2014

Keywords

Comments

Fuss-Catalan sequence is a(n,p,r) = r*binomial(np+r,n)/(np+r), this is the case p=11, r=2; also, g.f. satisfies: B(x) = {1 + x*B(x)^(p/r)}^r.

Crossrefs

Programs

  • Magma
    [2*Binomial(11*n+2,n)/(11*n+2): n in [0..30]]; // Vincenzo Librandi, Jan 01 2014
    
  • Mathematica
    Table[2 Binomial[11 n + 2, n]/(11 n + 2), {n, 0, 30}] (* Vincenzo Librandi, Jan 01 2014 *)
  • PARI
    a(n) = 2*binomial(11*n+2,n)/(11*n+2)
    for(n=0,20, print(a(n))) \\ Sequence
    
  • PARI
    {a(n)=local(B=1); for(i=0, n, B=(1+x*B^(11/2))^2+x*O(x^n)); polcoeff(B, n)}
    for (n=0,20, print(a(n))) \\ Generating Function
    
  • Sage
    [2*binomial(11*n+2,n)/(11*n+2) for n in range(20)] # F. Chapoton; Apr 29 2020

Formula

a(n) = 2*binomial(11*n+1,n-1)/n for n>0, a(0)=1. [Bruno Berselli, Jan 19 2014]