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.

A033852 Integers k such that j(k)*phi(k) = sigma(k), where j(n) = A033831(n).

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%I A033852 #20 Jul 20 2020 02:01:19
%S A033852 35,105,248,418,594,744,812,1254
%N A033852 Integers k such that j(k)*phi(k) = sigma(k), where j(n) = A033831(n).
%C A033852 a(9) > 10^7. - _Michel Marcus_, Nov 05 2014
%C A033852 a(9) > 10^8. - _Manfred Scheucher_, May 30 2015
%o A033852 (PARI) isok(n) = sumdiv(n, d, (d>=3) && (q=n/d) && (q>=1) && (q<=d-2))*eulerphi(n) == sigma(n); \\ _Michel Marcus_, Nov 05 2014
%Y A033852 Cf. A000010 (phi), A000203 (sigma), A033831.
%K A033852 more,nonn
%O A033852 1,1
%A A033852 _Naohiro Nomoto_