cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A238228 Numbers n such that if x=sigma(n)+phi(n)-tau(n)-n then n=sigma(x)+phi(x)-tau(x)-x.

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%I A238228 #10 Apr 10 2019 02:36:58
%S A238228 12,14,27,125,127
%N A238228 Numbers n such that if x=sigma(n)+phi(n)-tau(n)-n then n=sigma(x)+phi(x)-tau(x)-x.
%C A238228 a(6) > 2*10^11, if it exists. - _Giovanni Resta_, Apr 10 2019
%e A238228 Fixed points: 27,...
%e A238228 sigma(12) = 28, phi(12) = 4, tau(12) = 6 and 28 + 4 - 6 - 12 = 14.
%e A238228 sigma(14) = 24, phi(14) = 6, tau(14) = 4 and 24 + 6 - 4 - 14 = 12.
%p A238228 with(numtheory); P:=proc(q)local a,n;
%p A238228 for n from 1 to q do a:=sigma(n)+phi(n)-tau(n)-n;
%p A238228 if sigma(a)+phi(a)-tau(a)-a=n then print(n);
%p A238228 fi; od; end: P(10^6);
%Y A238228 Cf. A000005, A000010, A000203, A238225-A238227, A238229, A238230.
%K A238228 nonn,more
%O A238228 1,1
%A A238228 _Paolo P. Lava_, Feb 20 2014