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.

A165051 a(n) = image of n under the base-6 Kaprekar map n -> (n with digits sorted into descending order) - (n with digits sorted into ascending order).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 5, 0, 5, 10, 15, 20, 10, 5, 0, 5, 10, 15, 15, 10, 5, 0, 5, 10, 20, 15, 10, 5, 0, 5, 25, 20, 15, 10, 5, 0, 35, 35, 70, 105, 140, 175, 35, 0, 35, 70, 105, 140, 70, 35, 35, 70, 105, 140, 105, 70, 70, 70, 105, 140, 140, 105, 105, 105, 105, 140, 175, 140, 140, 140
Offset: 0

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Examples

			For n = 10, 10_10 = 14_6. So, a(10) = 41_6 - 14_6 = 25 - 10 = 15. - _Indranil Ghosh_, Feb 02 2017
		

Crossrefs

Cf. A165052.
In other bases: A164884 (base 2), A164993 (base 3), A165012 (base 4), A165032 (base 5), A165071 (base 7), A165090 (base 8), A165110 (base 9), A151949 (base 10).

Programs

  • Mathematica
    a[n_] := With[{dd = IntegerDigits[n, 6]}, FromDigits[ReverseSort[dd], 6] - FromDigits[Sort[dd], 6]];
    a /@ Range[0, 100] (* Jean-François Alcover, Jan 08 2020 *)