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A264912
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Number of 7-ascent sequences of length n with no consecutive repeated letters.
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2
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1, 1, 7, 56, 476, 4312, 41468, 422128, 4536140, 51328018, 610168496, 7604171722, 99154078394, 1350325442746, 19173655721912, 283420080801700, 4354942891383206, 69465537443190352, 1148784383085885884, 19673049517219904032, 348483690687062619926
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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`(n<1, 1, add(
`if`(j=i, 0, b(n-1, j, t+`if`(j>i, 1, 0))), j=0..t+7))
end:
a:= n-> (b(n-1, 0$2)):
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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