A293888 Number of sets of nonempty words with a total of n letters over septenary alphabet containing the seventh letter such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.

1, 8, 64, 394, 2390, 13297, 73408, 391136, 2079440, 10889818, 57092581, 297655901, 1556501986, 8132631687, 42662224461, 224171916523, 1183189769473, 6263511343367, 33311244068612, 177803544643092, 953453596829798, 5132942333604244, 27758886429083153

Offset

7,2

Links

Alois P. Heinz, Table of n, a(n) for n = 7..1000

Formula

a(n) = A293746(n) - A293745(n).

Crossrefs

Column k=7 of A293113.

Cf. A293745, A293746.

Sequence in context: A203437 A224132 A297376 * A218267 A189105 A181214

Adjacent sequences: A293885 A293886 A293887 * A293889 A293890 A293891

Keyword

nonn

Author

Alois P. Heinz, Oct 18 2017

Status

approved