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A180392
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Number of permutations of 1..n with both permutation and its inverse having exactly 2 maxima
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0
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0, 0, 1, 12, 66, 248, 739, 1880, 4260, 8832, 17061, 31108, 54054, 90168, 145223, 226864
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OFFSET
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1,4
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LINKS
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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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