A293799 Number of multisets of nonempty words with a total of n letters over quaternary alphabet containing the fourth 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, 5, 26, 107, 439, 1663, 6283, 22912, 83507, 298936, 1071564, 3804461, 13542785, 47964338, 170456957, 604293910, 2150604057, 7647190962, 27302834888, 97491596984, 349544018586, 1254140950775, 4517792721381, 16291580640312, 58974333255158, 213744923737227

Offset: 4

Author

Alois P. Heinz, Oct 16 2017

Keywords

• nonn

Links

• Alois P. Heinz, Table of n, a(n) for n = 4..1000

Crossrefs

Column k=4 of A293109.

Cf. A293733, A293734.

Formula

a(n) = A293734(n) - A293733(n).