

A274128


Numbers n such that n and n^2 are both a sum of two positive cubes.


1



39312, 251370, 314496, 432523, 948051, 1061424, 1536416, 2010960, 2515968, 3009825, 3460184, 4914000, 6786990, 6822900, 7154784, 7584408, 7825545, 8491392, 11678121, 12291328, 13484016, 16087680, 20127744, 24078600, 25501762, 25597377
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OFFSET

1,1


COMMENTS

Numbers n such that n^k is the sum of two positive cubes for all k not divisible by 3.
The restriction on the values of k is the result of Fermat's Last Theorem.
Inspiration was Taxicab number 39312. It is the least number with the property that sequence focuses on.


LINKS



EXAMPLE

251370 is a term because 251370 = 29^3 + 61^3 and 251370^2 = 2961^3 + 3339^3.


PROG

(PARI) isA003325(n) = for(k=1, sqrtnint(n\2, 3), ispower(nk^3, 3) && return(1));
lista(nn) = for(n=1, nn, if(isA003325(n) && isA003325(n^2), print1(n, ", ")));


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



