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A267189
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(Cubes of positive numbers) that are not the sum of three nonzero squares.
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2
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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
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1,2
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COMMENTS
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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)".
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LINKS
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Chai Wah Wu, Table of n, a(n) for n = 1..10000
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PROG
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(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) ; }
for(n=1, 200, if(!is(n^3), print1(n^3, ", "))); \\ Altug Alkan, Jan 18 2016
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CROSSREFS
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Cf. A000578, A004214, A134739.
Sequence in context: A188875 A344854 A223843 * A181480 A223948 A224151
Adjacent sequences: A267186 A267187 A267188 * A267190 A267191 A267192
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KEYWORD
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nonn
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AUTHOR
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N. J. A. Sloane, Jan 18 2016
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EXTENSIONS
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More terms from Altug Alkan, Jan 18 2016
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STATUS
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approved
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