A240612 Number of n-length words w over a 6-ary alphabet such that w is empty or a prefix z concatenated with letter a_i and i=1 or 0 < #(z,a_{i-1}) >= #(z,a_i), where #(z,a_i) counts the occurrences of the i-th letter in z.

1, 1, 2, 5, 14, 46, 165, 650, 2742, 12195, 56388, 267382, 1291017, 6304776, 31043333, 153739806, 764663187, 3817811679, 19117378411, 96034890298, 483633087406, 2442935438558, 12369440072730, 62816259353597, 319763315261222, 1632483727134416, 8354058837330795

Offset

0,3

Links

Table of n, a(n) for n=0..26.

Crossrefs

Column k=6 of A240608.

Sequence in context: A124527 A149898 A240611 * A240613 A240614 A240615

Adjacent sequences: A240609 A240610 A240611 * A240613 A240614 A240615

Keyword

nonn

Author

Alois P. Heinz, Apr 09 2014

Status

approved