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A238231
Numbers n such that if x=phi(n)*tau(n)-sigma(n)-n then n=phi(x)*tau(x)-sigma(x)-x.
0
376, 594, 846, 1178, 1222, 46498, 65198
OFFSET
1,1
COMMENTS
a(8) > 2*10^9. - Giovanni Resta, Mar 26 2014
EXAMPLE
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.
MAPLE
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);
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Paolo P. Lava, Feb 20 2014
STATUS
approved