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A090347
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Number of labeled trees with n nodes and even number of leaves minus number of labeled trees with n nodes and odd number of leaves.
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0
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1, 3, 8, 5, -156, -1253, 48, 116937, 1236140, -4517689, -317599800, -3473788019, 43408737540, 2033846838675, 19004486417504, -643679274285679, -24665731809676452, -135665006897593601, 15018201730467027960
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OFFSET
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2,2
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LINKS
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FORMULA
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Sum_{k=0..n} (-1)^k*n!/k!*stirling2(n-2, n-k).
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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