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.

A386010 Numbers z such that there exist two integers 0 such that sigma(x)*sigma(y)*sigma(z) = (x + y + z)^3.

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%I A386010 #4 Jul 20 2025 16:38:41
%S A386010 120,672,1188,1740,2556,11172,11556,11628,27312,32136,41412,41952,
%T A386010 42168
%N A386010 Numbers z such that there exist two integers 0<x<=y<=z such that sigma(x)*sigma(y)*sigma(z) = (x + y + z)^3.
%C A386010 The numbers x, y and z form a GM-amicable triple (GM = Geometric Mean). See Dimitrov link. An amicable triple forms a GM-amicable triple, so the larger member of an amicable triple A125492 is a term of this sequence.
%H A386010 S. I. Dimitrov, <a href="https://arxiv.org/abs/2408.07387">Generalizations of amicable numbers</a>, arXiv:2408.07387 [math.NT], 2024.
%e A386010 (1080, 1092, 1188) is such a triple because sigma(1080)*sigma(1092)*sigma(1188) = (1080 + 1092 + 1188)^3.
%Y A386010 Cf. A000203, A125492, A383932.
%K A386010 nonn,hard,more
%O A386010 1,1
%A A386010 _S. I. Dimitrov_, Jul 14 2025