

A267189


(Cubes of positive numbers) that are not the sum of three nonzero squares.


2



1, 8, 64, 343, 512, 3375, 4096, 12167, 21952, 29791, 32768, 59319, 103823, 166375, 216000, 250047, 262144, 357911, 493039, 658503, 778688, 857375, 1092727, 1367631, 1404928, 1685159, 1906624, 2048383, 2097152, 2460375, 2924207, 3442951, 3796416, 4019679, 4657463, 5359375, 6128487
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OFFSET

1,2


COMMENTS

This is the intersection of A004214 and A000578.
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)".


LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000


PROG

(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(na^2b^2), return(1) ) ; b++ ; ) ; a++ ; ) ; return(0) ; }
for(n=1, 200, if(!is(n^3), print1(n^3, ", "))); \\ Altug Alkan, Jan 18 2016


CROSSREFS

Cf. A000578, A004214, A134739.
Sequence in context: A189190 A188875 A223843 * A181480 A223948 A224151
Adjacent sequences: A267186 A267187 A267188 * A267190 A267191 A267192


KEYWORD

nonn


AUTHOR

N. J. A. Sloane, Jan 18 2016


EXTENSIONS

More terms from Altug Alkan, Jan 18 2016


STATUS

approved



