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.

A113506 Maximum element in the continued fraction expansion of F(n+1)^5/F(n)^5 where F=A000045.

Original entry on oeis.org

1, 32, 7, 12, 17, 46, 3042, 319, 835, 2188, 5730, 375131, 39282, 102845, 269253, 704915, 46137317, 4831563, 12649196, 33116027, 86698886, 5674515856, 594243013, 1555748409, 4073002214, 10663258234, 697919312217, 73087059232
Offset: 1

Views

Author

Benoit Cloitre, Jan 11 2006

Keywords

Crossrefs

Cf. A113500.

Programs

  • Mathematica
    Max[ContinuedFraction[#[[2]]/#[[1]]]]&/@Partition[Fibonacci[ Range[ 30]]^5,2,1] (* Harvey P. Dale, May 27 2018 *)
  • PARI
    a(n)=vecmax(contfrac(fibonacci(n+1)^5/fibonacci(n)^5))

Formula

5*a(5n)=F(10n+1)-(-1)^n-5; 5*a(5n+1)=F(10n+3)-2*(-1)^n-5; a(5n+2)=5*F(10n+5)+7*(-1)^n-1; 5a(5n+3)=F(10n+7)-3*(-1)^n-5; 5a(5n+4)=F(10n+9)+(-1)^n-5.
Empirical g.f.: x*(6*x^19 -5*x^17 +x^16 -x^15 -732*x^14 -x^13 +593*x^12 -107*x^11 +118*x^10 -743*x^9 +94*x^8 -327*x^7 +786*x^6 +93*x^5 -5*x^4 -5*x^3 +25*x^2 -31*x -1) / ((x -1) * (x +1) * (x^2 -3*x +1) * (x^4 -x^3 +x^2 -x +1) * (x^4 -x^3 +6*x^2 +4*x +1) * (x^4 +4*x^3 +6*x^2 -x +1)). - Colin Barker, Jun 17 2013