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.

A071154 Totally balanced decimal numbers: if we assign the weight w(d) = d-1 to each digit d (i.e., w(0) = -1, w(1) = 0, ..., w(9) = 8) and then read the digits of the term from left to right, the partial sum of the weights is never negative and the total weighted sum is zero.

Original entry on oeis.org

1, 11, 20, 111, 120, 201, 210, 300, 1111, 1120, 1201, 1210, 1300, 2011, 2020, 2101, 2110, 2200, 3001, 3010, 3100, 4000, 11111, 11120, 11201, 11210, 11300, 12011, 12020, 12101, 12110, 12200, 13001, 13010, 13100, 14000, 20111, 20120, 20201
Offset: 1

Views

Author

Antti Karttunen, May 14 2002

Keywords

Comments

The initial portion of this sequence (up to the 6917th term) is equal to A071153 (Łukasiewicz words for rooted plane trees) sorted in ascending order.

Crossrefs

Subset of A061384. Superset of A071161.
Cf. A014486 (totally balanced binary numbers), A071153.

Programs

  • PARI
    isok(n) = {my(s = 0); my(d = digits(n)); for (k=1, #d, s += d[k]-1; if (s<0, return (0));); if (s, 0, 1);} \\ Michel Marcus, Oct 16 2015