A293115 Number of sets of nonempty words with a total of 2n letters over n-ary alphabet containing the n-th 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, 1, 8, 53, 410, 3576, 35878, 391136, 4666521, 59096165, 797628339, 11282268353, 167582833398, 2587994886476, 41585338511800, 690912445945576, 11870082701946292, 209995330141487944, 3824511903396303251, 71496027436457015058, 1371314535020854180410
Offset: 0
Keywords
Links
- Alois P. Heinz, Table of n, a(n) for n = 0..26
Formula
a(n) = A293113(2n,n).