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.

A256618 Index i such that A121217(i) = n, or 0 if no such i exists.

Original entry on oeis.org

1, 2, 3, 4, 10, 5, 13, 6, 7, 8, 21, 9, 26, 11, 12, 16, 34, 14, 35, 18, 15, 19, 47, 17, 20, 24, 25, 29, 54, 22, 61, 31, 23, 32, 40, 27, 68, 33, 28, 41, 77, 30, 82, 43, 38, 45, 91, 39, 42, 46, 36, 48, 100, 50, 53, 44, 37, 52, 109, 51, 118, 59, 58, 62, 55, 60
Offset: 1

Views

Author

Reinhard Zumkeller, Apr 05 2015

Keywords

Comments

If A121217 is a permutation, as conjectured, then this is the inverse permutation.

Crossrefs

Cf. A121217.

Programs

  • Haskell
    import Data.List (elemIndex); import Data.Maybe (fromJust)
    a256618 = (+ 1) . fromJust . (`elemIndex` a121217_list)