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A241695
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Number of Carlitz compositions of n with exactly five descents.
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2
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8, 43, 159, 497, 1365, 3412, 7959, 17529, 36820, 74341, 145037, 274632, 506546, 912668, 1610174, 2787338, 4742439, 7942378, 13109810, 21351242, 34344574, 54611144, 85907033, 133783286, 206382165, 315561476, 478474684, 719778651, 1074701635, 1593288000
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OFFSET
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15,1
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COMMENTS
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No two adjacent parts of a Carlitz composition are equal.
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LINKS
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MAPLE
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b:= proc(n, i) option remember; `if`(n=0, 1,
convert(series(add(`if`(i=j, 0, b(n-j, j)*
`if`(j<i, x, 1)), j=1..n), x, 6), polynom))
end:
a:= n-> coeff(b(n, 0), x, 5):
seq(a(n), n=15..50);
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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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