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.
%I A114077 #16 Sep 08 2022 08:45:23 %S A114077 1,3,119,357,2522,6305,6596,6604,7566,18915,19788,19812,20520,24347, %T A114077 24353,26068,26082,28126,47959,58520,64790,65205,70315,73041,73059, %U A114077 73636,75460,78204,84378,143877,156519,164920,175560,194370,210945,212660,220908,226380 %N A114077 Numbers k such that phi(k)*sigma(k) is a cube. %D A114077 J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 119, p. 41, Ellipses, Paris 2008. %H A114077 Amiram Eldar, <a href="/A114077/b114077.txt">Table of n, a(n) for n = 1..6000</a> %e A114077 phi(357) * sigma(357) = 110592 = 48^3. %t A114077 Select[Range[10^5], IntegerQ @ Surd[EulerPhi[#] * DivisorSigma[1, #], 3] &] (* _Amiram Eldar_, Sep 19 2019 *) %o A114077 (PARI) isok(n) = ispower(eulerphi(n)*sigma(n), 3); \\ _Michel Marcus_, Jan 22 2014 %o A114077 (Magma) [k:k in [1..230000]| IsPower(EulerPhi(k)*DivisorSigma(1,k),3)]; // _Marius A. Burtea_, Sep 19 2019 %Y A114077 Cf. A062354. %K A114077 nonn %O A114077 1,2 %A A114077 _Giovanni Resta_, Feb 13 2006