A213876 Number of words w where each letter of the 6-ary alphabet occurs n times and for every prefix z of w we have #(z,a_i) = 0 or #(z,a_i) >= #(z,a_j) for all j>i and #(z,a_i) counts the occurrences of the i-th letter in z.

1, 720, 10395, 3864040, 4622269345, 10915151070941, 40684710729862072, 211109968702038259993, 1409438188685787895321841, 11481253272835564584899247346, 109898940874611419792791074271620, 1202306852636261419990922606451803760

Offset: 0

Author

Alois P. Heinz, Jun 23 2012

Keywords

• nonn

Examples

			a(0) = 1: the empty word.
a(1) = 720: abcdef, abcdfe, abcedf, ..., fedbca, fedcab, fedcba.
a(2) = 10395: aabbccddeeff, aabbccddefef, aabbccddfeef, ..., fedcaabbcdef, fedcababcdef, fedcbaabcdef.
		

Crossrefs

Column k=6 of A213275.