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A362308
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Triangle read by rows. Number of perfect matchings by number of connected components.
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0
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1, 0, 1, 0, 2, 1, 0, 10, 4, 1, 0, 74, 24, 6, 1, 0, 706, 188, 42, 8, 1, 0, 8162, 1808, 350, 64, 10, 1, 0, 110410, 20628, 3426, 568, 90, 12, 1, 0, 1708394, 273064, 38886, 5696, 850, 120, 14, 1
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OFFSET
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0,5
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COMMENTS
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The exact definition is given in Sokal and Zeng. See section 4.4 and theorem 4.6.
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LINKS
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FORMULA
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T(n, k) = T(n, k-1) - T(n-1, k-2) - (2*n - k - 1)/(k - 1) * T(n - 1, k - 1) for k > 1. - Detlef Meya, Dec 21 2023
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EXAMPLE
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Table T(n, k) begins:
[0] 1;
[1] 0, 1;
[2] 0, 2, 1;
[3] 0, 10, 4, 1;
[4] 0, 74, 24, 6, 1;
[5] 0, 706, 188, 42, 8, 1;
[6] 0, 8162, 1808, 350, 64, 10, 1;
[7] 0, 110410, 20628, 3426, 568, 90, 12, 1;
[8] 0, 1708394, 273064, 38886, 5696, 850, 120, 14, 1;
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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