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.

A226911 Remainder modulo n of the sum of the letters of the English word(s) for n (A073327: a=1, ..., z=26).

Original entry on oeis.org

0, 0, 2, 0, 2, 4, 2, 1, 6, 9, 8, 3, 8, 6, 5, 0, 7, 1, 10, 7, 15, 11, 2, 23, 24, 3, 10, 16, 4, 10, 10, 30, 24, 24, 2, 8, 17, 35, 25, 4, 36, 16, 11, 12, 36, 44, 8, 37, 28, 16, 49, 20, 16, 18, 53, 6, 17, 57, 49, 37, 9, 31, 27, 29, 9, 17, 28, 10, 1, 40, 2, 24, 20, 22, 2, 10, 21, 3
Offset: 1

Views

Author

Eric Angelini and M. F. Hasler, Jun 22 2013

Keywords

Comments

By definition, a(n) < n so iterated application of this function to any initial value n will create a strictly decreasing sequence ending in 0.

Crossrefs

Programs

  • Maple
    f:= proc(n) local S;
       uses StringTools;
      S:= Select(IsAlpha,convert(n,english));
      convert(map(`-`,convert(S,bytes),96),`+`) mod n
    end proc:
    map(f, [$1..100]); # Robert Israel, Jun 12 2019
  • Mathematica
    a[n_] := Mod[Total@ Flatten[ ToCharacterCode[#] - 96 & /@ Characters@ StringDelete[ IntegerName[n], Except@ LetterCharacter]], n] (* after Michael De Vlieger in A362065 *); Array[a, 78] (* Robert G. Wilson v, Apr 22 2023 *)
  • PARI
    A226911 = n->A073327(n)%n

Formula

a(n) = A073327(n) mod n.
It appears that a(n) = A073327(n) for n > 279. - Robert Israel, Jun 12 2019