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a(n) is the number of integers m > 1 such that sigma(m) = tau(m)^n, with a(1) = 1.
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%I #16 Dec 11 2021 11:08:42

%S 1,1,1,2,3,3,3,5,4,5,5,7,9,5,6,2,7,7,5,6,5,9,6,11,6,12,10,12,14,11,13,

%T 21,16,20,19,20,19,21,21,19,17,21,18,22,19,22,20,17,17,15,23,14,17,12,

%U 16,9,11,12,10,9,9,7,10,3,8,7,6,3,7,4,4,4,3,3,2

%N a(n) is the number of integers m > 1 such that sigma(m) = tau(m)^n, with a(1) = 1.

%C a(n) is the number of integers m such that A334455(m) = n.

%C Conjecture: a(n) > 0 except for n = 76 and n = 81.

%H Rémy Sigrist, <a href="/A349837/b349837.txt">Table of n, a(n) for n = 1..5000</a>

%H Rémy Sigrist, <a href="/A349837/a349837.gp.txt">PARI program for A349837</a>

%o (PARI) See Links section.

%Y Cf. A000005 (tau), A000203 (sigma), A334455, A349006, A349007, A349838.

%K nonn

%O 1,4

%A _Rémy Sigrist_, Dec 01 2021