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Number of words w where each letter of the 5-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.
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%I #5 Jun 24 2012 12:58:39

%S 1,120,945,87595,19558470,7236515981,3745777177366,2468722942369153,

%T 1953740543358042205,1785201362960729511070,1831976833971352074708780,

%U 2068976591723429552651743620,2532392303303120865350779766160,3319547855302819899374947284511390

%N Number of words w where each letter of the 5-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.

%H Alois P. Heinz, <a href="/A213875/b213875.txt">Table of n, a(n) for n = 0..50</a>

%e a(0) = 1: the empty word.

%e a(1) = 120: abcde, abced, abdce, ..., edbca, edcab, edcba, (all permutations of 5 letters).

%e a(2) = 945: aabbccddee, aabbccdede, aabbccedde, ..., edcaabbcde, edcababcde, edcbaabcde.

%Y Column k=5 of A213275.

%K nonn

%O 0,2

%A _Alois P. Heinz_, Jun 23 2012