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A238231
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Numbers n such that if x=phi(n)*tau(n)-sigma(n)-n then n=phi(x)*tau(x)-sigma(x)-x.
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0
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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Fixed points: 376,...
phi(594) = 180, tau(594) = 16, sigma(594) = 1440 and 180*16 - 1440 - 594 = 846.
phi(846) = 276, tau(846) = 12, sigma(846) = 1872 and 276*12 - 1872 - 846 = 594.
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MAPLE
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with(numtheory); P:=proc(q)local a, n;
for n from 1 to q do a:=phi(n)*tau(n)-sigma(n)-n;
if a>0 and phi(a)*tau(a)-sigma(a)-a=n then print(n);
fi; od; end: P(10^6);
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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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