A213292 Number of n-length words w over 4-ary alphabet such that for every prefix z of w we have #(z,a_i) = 0 or #(z,a_i) >= #(z,a_j) for all j>i and #(z,a_i) counts the occurrences of the i-th letter in z.

1, 4, 16, 46, 118, 276, 712, 1805, 4895, 13280, 37993, 109386, 328219, 992413, 3101399, 9764376, 31580645, 102797899, 342075208, 1144125506, 3896297053, 13319243655, 46206520968, 160729837020, 565901313043, 1996113320841, 7111795754941, 25369213794266

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..130

Crossrefs

Column k=4 of A213276.

Sequence in context: A374262 A007315 A055342 * A174836 A244252 A369401

Adjacent sequences: A213289 A213290 A213291 * A213293 A213294 A213295

Keyword

nonn

Author

Alois P. Heinz, Jun 08 2012

Status

approved