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Number of n-length words w over a 10-ary alphabet {a1,a2,...,a10} such that #(w,a1) >= #(w,a2) >= ... >= #(w,a10) >= 0, where #(w,x) counts the letters x in word w.
4

%I #16 Sep 21 2017 11:33:50

%S 1,1,3,10,47,246,1602,11481,95503,871030,8879558,58412751,473076122,

%T 3607903547,29782240841,241773783075,2137404383423,18482746670342,

%U 173563010955990,1554987178737075,15169020662626702,126731980207937625,1160565179374262951

%N Number of n-length words w over a 10-ary alphabet {a1,a2,...,a10} such that #(w,a1) >= #(w,a2) >= ... >= #(w,a10) >= 0, where #(w,x) counts the letters x in word w.

%C Differs from A005651 first at n=11: a(11) = 58412751 != A005651(11) = 98329551.

%H Alois P. Heinz, <a href="/A226880/b226880.txt">Table of n, a(n) for n = 0..1000</a>

%p b:= proc(n, i, t) option remember;

%p `if`(t=1, 1/n!, add(b(n-j, j, t-1)/j!, j=i..n/t))

%p end:

%p a:= n-> n!*b(n, 0, 10):

%p seq(a(n), n=0..30);

%Y Column k=10 of A226873.

%K nonn

%O 0,3

%A _Alois P. Heinz_, Jun 21 2013