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OFFSET
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1,1
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COMMENTS
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Question: Are there any odd terms?
No other terms < 2^31.
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LINKS
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PROG
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(PARI)
A007947(n) = factorback(factorint(n)[, 1]);
isA326145(n) = { my(b=A007947(n), t=n-b, u = (sigma(n)-b)-n); (gcd(t, u)==t); };
\\ Or alternatively as:
isA326145(n) = { my(t=A326143(n), u=A066503(n)); ((!u && !t)||(u && !(t%u))); };
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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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