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A082426
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a(1)=1, a(n)=n*(a(n-1)+a(n-2)+...+a(2)+a(1)) + 2.
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0
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1, 3, 10, 49, 301, 2161, 17641, 161281, 1632961, 18144001, 219542401, 2874009601, 40475635201, 610248038401, 9807557760001, 167382319104001, 3023343138816001, 57621363351552001, 1155628453883904001
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OFFSET
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1,2
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COMMENTS
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Concatenate all the permutations of 1..n in lexicographical order. a(n) is the number of ascending runs. [David Scambler, May 26 2011]
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LINKS
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FORMULA
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for n>=2 a(n) = ceiling(n*(2*e-9/2)*n!)
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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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