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A139307
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(2^(2p - 1)) - 1, where p is A000043(n).
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3
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7, 31, 511, 8191, 33554431, 8589934591, 137438953471, 2305843009213693951, 2658455991569831745807614120560689151, 191561942608236107294793378393788647952342390272950271
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OFFSET
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1,1
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COMMENTS
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Ultraperfect numbers (A139306) minus 1.
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LINKS
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FORMULA
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EXAMPLE
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a(5)=33554431 because A000043(5)=13 and (2^(2*13 - 1))-1 = 2^25 - 1 = 33554431.
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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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