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.

A349007 a(1) = 1; for n > 1, a(n) is the largest number m such that sigma(m) = tau(m)^n or 0 if no such m exists.

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%I A349007 #10 Dec 13 2021 17:17:46
%S A349007 1,3,7,2667,27559,677207307,225735769,698915267211,29587412978599,
%T A349007 811637999283747,16907189874529,12200855315219510767697163,
%U A349007 254155396405925065290841,878412242330556407427,1074593611687774330088252281,16138807601873739769,37471768236581557067194399
%N A349007 a(1) = 1; for n > 1, a(n) is the largest number m such that sigma(m) = tau(m)^n or 0 if no such m exists.
%C A349007 See A051281 for numbers m such that sigma(m) = tau(m)^k where k = integer.
%C A349007 a(n) = 0 for n = 76, 81, ...
%H A349007 Rémy Sigrist, <a href="/A349007/a349007.gp.txt">PARI program for A349007</a>
%e A349007 a(4) = 2667 because 2667 is the largest number m such that sigma(m) = tau(m)^4; sigma(2667) = 4096 = tau(2667)^4  = 8^4.
%o A349007 (PARI) See Links section.
%Y A349007 Subsequence of A051281.
%Y A349007 Cf. A000005 (tau), A000203 (sigma), A334455, A349006.
%K A349007 nonn
%O A349007 1,2
%A A349007 _Jaroslav Krizek_, Nov 05 2021