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A325638
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Numbers m such that sigma(m) can be obtained as the base-2 carryless product of 2m and some k.
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4
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6, 28, 456, 496, 6552, 8128, 30240, 31452, 32760, 429240, 2178540, 7505976, 23569920, 33550336, 45532800, 142990848, 1379454720
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OFFSET
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1,1
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COMMENTS
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Numbers m for which A091255(2m, sigma(m)) = 2m.
Conjecture: all terms are even. If this is true, then there are no odd perfect numbers. See also conjectures in A325639 and in A325808.
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LINKS
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PROG
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(PARI)
A091255sq(a, b) = fromdigits(Vec(lift(gcd(Pol(binary(a))*Mod(1, 2), Pol(binary(b))*Mod(1, 2)))), 2);
A325635(n) = A091255sq(n+n, sigma(n));
isA325638(n) = ((n+n)==A325635(n));
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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