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A334777
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Total number of local maxima in all permutations of 2 indistinguishable copies of 1..n.
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3
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1, 9, 195, 7140, 396900, 31185000, 3291888600, 449513064000, 77111922888000, 16235185926960000, 4116213602701200000, 1237059394731800640000, 434864246413372776000000, 176784623645708110032000000, 82297894534015170170160000000, 43496460979945066988294400000000
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) = Sum_{k=1..n} k*A334774(n,k).
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PROG
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(PARI) \\ PeaksBySig defined in A334774.
a(n)={my(u=PeaksBySig(vector(n, i, 2), [0..n-1])); sum(k=1, #u, k*u[k])}
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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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