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A209412
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Number of nonisomorphic semigroups of order 2^n.
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0
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OFFSET
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0,2
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COMMENTS
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This is to A000679 as semigroups are to groups.
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LINKS
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FORMULA
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EXAMPLE
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a(3) = 3684030417 because there are 3684030417 nonisomorphic semigroups of order 2^3 = 8.
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CROSSREFS
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Cf. A000079, A000679 Number of groups of order 2^n, A027851 Number of nonisomorphic semigroups of order n.
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KEYWORD
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nonn,hard
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AUTHOR
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STATUS
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approved
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