A321843 Number of words w of length n such that each letter of the septenary alphabet is used at least once and 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.

5040, 20160, 105840, 438480, 1941390, 7981380, 34199295, 143278023, 618279060, 2662235895, 11732993885, 52051997928, 235469637340, 1076082576890, 5001152965060, 23506245393141, 112121385673903, 540819706031799, 2642597365003695, 13049933076792172

Offset

7,1

Links

Table of n, a(n) for n=7..26.

Crossrefs

Column k=7 of A257783.

Sequence in context: A190107 A090393 A147632 * A226886 A284204 A159083

Adjacent sequences: A321840 A321841 A321842 * A321844 A321845 A321846

Keyword

nonn

Author

Alois P. Heinz, Nov 19 2018

Status

approved