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.

A297170 a(n) = gcd(phi(n), sigma(n)-n).

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%I A297170 #5 Mar 03 2018 17:34:39
%S A297170 1,1,1,1,1,2,1,1,2,4,1,4,1,2,1,1,1,3,1,2,1,2,1,4,2,4,1,4,1,2,1,1,5,4,
%T A297170 1,1,1,2,1,2,1,6,1,20,3,2,1,4,2,1,1,2,1,6,1,8,1,4,1,4,1,2,1,1,1,2,1,2,
%U A297170 1,2,1,3,1,4,1,4,1,6,1,2,2,4,1,4,1,2,1,4,1,24,3,4,5,2,1,4,1,1,3,1,1,2,1,2,3
%N A297170 a(n) = gcd(phi(n), sigma(n)-n).
%H A297170 Antti Karttunen, <a href="/A297170/b297170.txt">Table of n, a(n) for n = 1..65537</a>
%F A297170 a(n) = gcd(A000010(n), A001065(n)).
%o A297170 (PARI) A297170(n) = gcd(eulerphi(n),sigma(n)-n);
%Y A297170 Cf. A000010, A000203, A001065, A009223.
%K A297170 nonn
%O A297170 1,6
%A A297170 _Antti Karttunen_, Mar 03 2018