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A226877
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Number of n-length words w over a 7-ary alphabet {a1,a2,...,a7} such that #(w,a1) >= #(w,a2) >= ... >= #(w,a7) >= 0, where #(w,x) counts the letters x in word w.
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4
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1, 1, 3, 10, 47, 246, 1602, 11481, 55183, 326710, 1924358, 11843151, 76569242, 494393147, 3419744681, 20455085475, 133157018303, 860006815622, 5660947113750, 37583646117555, 249434965500622, 1713067949756985, 11030202759647591, 73747039462964885
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OFFSET
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0,3
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LINKS
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MAPLE
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b:= proc(n, i, t) option remember;
`if`(t=1, 1/n!, add(b(n-j, j, t-1)/j!, j=i..n/t))
end:
a:= n-> n!*b(n, 0, 7):
seq(a(n), n=0..30);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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