A240616 Number of n-length words w over a 10-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, 651, 2771, 12638, 61398, 315562, 1709960, 9723253, 57831688, 358445901, 2306799588, 15354546420, 105275618325, 740481162174, 5321875886529, 38940082552276, 289132258826130, 2172495189822333, 16480880960094288, 125993420982428718

Offset

0,3

Links

Table of n, a(n) for n=0..25.

Crossrefs

Column k=10 of A240608.

Sequence in context: A240613 A240614 A240615 * A240617 A001680 A275424

Adjacent sequences: A240613 A240614 A240615 * A240617 A240618 A240619

Keyword

nonn

Author

Alois P. Heinz, Apr 09 2014

Status

approved