A178096 Cube of n is equal to sum of four positive distinct squares; n^3=a^2+b^2+c^2+d^2; a>b>c>d>0.
5, 6, 7, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 55, 56, 57
Offset: 1
Keywords
Programs
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Mathematica
z=100;lst={};Do[a2=a^2;Do[b2=b^2;Do[c2=c^2;Do[d2=d^2;e2=a2+b2+c2+d2;e=e2^(1/3);If[IntegerQ[e],AppendTo[lst,e]],{d,c-1,1,-1}],{c,b-1,1,-1}],{b,a-1,1,-1}],{a,1,z}];Union@lst
Formula
{n: n^3 in A004433}. - R. J. Mathar, Jun 15 2018
Extensions
Terms > 33 from R. J. Mathar, Jun 15 2018
Comments