A273822 Integers n such that n^3 + 1 is the average of two positive cubes.

27, 227, 335, 2387, 9299, 104571, 113519, 118499, 212343, 258999, 328499, 455600, 699891, 820755, 971360, 977051, 1059239, 1119723, 1193631, 1421367, 1604084, 2231999, 2794067, 4191431, 5450948, 6054611, 6769607, 7672391, 7760639, 7875035, 8091615, 9606203, 15511268

Offset

1,1

Comments

Integers n such that n^3 + 1 is the average of two distinct positive cubes.

Links

Table of n, a(n) for n=1..33.

Example

27 is a term because 27^3 + 1 = (4^3 + 34^3)/2.

Prog

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

Crossrefs

Cf. A001093, A003325.

Sequence in context: A222994 A125364 A126522 * A027500 A069979 A183806

Adjacent sequences: A273819 A273820 A273821 * A273823 A273824 A273825

Keyword

nonn

Author

Altug Alkan, May 31 2016

Extensions

a(9)-a(12) from Giovanni Resta, Jun 01 2016

a(13)-a(33) from Chai Wah Wu, Jun 19 2016

Status

approved