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A082551
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Denote sigma(n)-n by s(n); a(n)=1 if s(n)>n, a(n)=0 if s(n)=n, a(n)=-1 if s(n)<n.
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2
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-1, -1, -1, -1, -1, 0, -1, -1, -1, -1, -1, 1, -1, -1, -1, -1, -1, 1, -1, 1, -1, -1, -1, 1, -1, -1, -1, 0, -1, 1, -1, -1, -1, -1, -1, 1, -1, -1, -1, 1, -1, 1, -1, -1, -1, -1, -1, 1, -1, -1, -1, -1, -1, 1, -1, 1, -1, -1, -1, 1, -1, -1, -1, -1, -1, 1, -1, -1, -1, 1, -1, 1, -1
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OFFSET
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1,1
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LINKS
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FORMULA
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MAPLE
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signum( numtheory[sigma](n)-2*n) ;
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MATHEMATICA
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Table[Sign[DivisorSigma[1, n] - 2*n], {n, 1, 100}] (* Amiram Eldar, Mar 15 2024 *)
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PROG
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CROSSREFS
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KEYWORD
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easy,sign
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AUTHOR
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Hanoch M. bin (hanochb(AT)shiron.com), May 12 2003
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STATUS
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approved
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