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A239837
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Number of ordered pairs of permutation functions on n elements satisfying f(f(x)) = g(f(g(x))).
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2
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1, 1, 2, 12, 96, 600, 6480, 85680, 1048320, 16692480, 315705600, 5468601600, 117834393600, 2951607859200, 68958028339200, 1856897602560000, 58228124258304000, 1721171464556544000, 56379302852640768000, 2111880588197732352000, 76033053559536353280000
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OFFSET
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0,3
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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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EXTENSIONS
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STATUS
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approved
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