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.

A081462 Consider the mapping f(a/b) = (a^2+b^3)/(a^3+b^2) from rationals to rationals. Starting with 1/2 (a=1, b=2) and applying the mapping to each new (reduced) rational number gives 1/2, 9/5, 103/377, ... . Sequence gives values of the denominators.

Original entry on oeis.org

2, 5, 377, 617428, 19241552119440973526245, 6579843627298148620615676439841151690983233028443241
Offset: 1

Views

Author

Amarnath Murthy, Mar 22 2003

Keywords

Crossrefs

Programs

  • PARI
    {r=1/2; for(n=1,7,a=numerator(r); b=denominator(r); print1(b,","); r=(a^2+b^3)/(a^3+b^2))}

Extensions

Edited and extended by Klaus Brockhaus, Mar 28 2003