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A279039
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Odd numbers n such that 2^n == 1 (mod sigma(n)).
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1
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OFFSET
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1,2
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LINKS
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EXAMPLE
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25 is a term because it is an odd number and sigma(25) divides 2^25 - 1.
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PROG
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(PARI) is(n)=Mod(2, sigma(n))^n==1&&n%2==1;
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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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STATUS
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approved
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