|
%I #17 Feb 02 2016 03:36:55
%S 1,8,64,343,512,3375,4096,12167,21952,29791,32768,59319,103823,166375,
%T 216000,250047,262144,357911,493039,658503,778688,857375,1092727,
%U 1367631,1404928,1685159,1906624,2048383,2097152,2460375,2924207,3442951,3796416,4019679,4657463,5359375,6128487
%N (Cubes of positive numbers) that are not the sum of three nonzero squares.
%C This is the intersection of A004214 and A000578.
%C The original definition of A134739 was ambiguous - this is the second way it could have been interpreted. The other way, now the official definition of A134739, being "Cubes of (positive numbers that are not the sum of three nonzero squares)".
%H Chai Wah Wu, <a href="/A267189/b267189.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) is(n) = { my(a, b) ; a=1; while(a^2+1<n, b=1 ; while(b<=a && a^2+b^2<n, if(issquare(n-a^2-b^2), return(1) ) ; b++ ; ) ; a++ ; ) ; return(0) ; }
%o for(n=1, 200, if(!is(n^3), print1(n^3, ", "))); \\ _Altug Alkan_, Jan 18 2016
%Y Cf. A000578, A004214, A134739.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Jan 18 2016
%E More terms from _Altug Alkan_, Jan 18 2016
|
