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.

A046755 Numbers k such that d(k)^3 divides k.

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%I A046755 #21 Aug 07 2019 04:59:58
%S A046755 1,625,6561,21952,32768,64000,98304,117649,163840,229376,360448,
%T A046755 425984,557056,622592,753664,950272,1015808,1212416,1343488,1362944,
%U A046755 1409024,1540096,1736704,1933312,1998848,2195456,2326528,2392064,2588672
%N A046755 Numbers k such that d(k)^3 divides k.
%C A046755 Proper subset of both A033950 and A046754. If two terms in the sequence are coprime then their product is also in the sequence.
%H A046755 Amiram Eldar, <a href="/A046755/b046755.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..1000 from Donovan Johnson)
%e A046755 If k = 21952, d(k) = sigma(0,k) = 28. Its 3rd power is 21952, which divides k.
%e A046755 a(103) = 14385152 = (2^15)*439 with 32 divisors and 14385152/(32^3) = 439; 2^15*prime is a typical form of terms in the sequence that have 32 divisors.
%t A046755 Select[ Range[ 1, 14500000 ], IntegerQ[ #/(DivisorSigma[ 0, # ])^3 ]& ]
%Y A046755 Cf. A033950, A046754, A046756.
%K A046755 nonn
%O A046755 1,2
%A A046755 _Labos Elemer_