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%I #4 Jun 24 2012 12:57:41
%S 1,1,19,1075,115955,19558470,4622269345,1428739165560,551211090935595,
%T 256653852463806955,140633739174235040170,88931024447225475920050,
%U 63897452586372538310261555,51509615229665486538200354125,46102293227619069563429377126200
%N Number of words w where each letter of the n-ary alphabet occurs 4 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.
%e a(0) = 1: the empty word.
%e a(1) = 1: aaaa.
%e a(2) = 19: aaaabbbb, aaababbb, aaabbabb, aaabbbab, aabaabbb, aabababb, aababbab, aabbaabb, aabbabab, abaaabbb, abaababb, abaabbab, ababaabb, abababab, baaaabbb, baaababb, baaabbab, baabaabb, baababab.
%Y Row n=4 of A213275.
%K nonn
%O 0,3
%A _Alois P. Heinz_, Jun 23 2012