A293651 Sum of two (possibly negative) coprime cubes in at least 3 ways, but not the sum of 2 noncoprime cubes.

3367, 68913, 152551, 195841, 625177, 684019, 1147627, 1548729, 2113921, 2628073, 2985983, 3242197, 3442887, 4488211, 4663295, 4931101, 5318677, 7194889, 8741691, 9667693, 14110579, 15072967, 15438185, 16776487, 21463407, 22910797, 24769502, 26122131, 26460217

Offset: 1

Author

Rosalie Fay, Oct 16 2017

Keywords

• nonn

Comments

Not every term is cubefree; some are sb^3 where s is in A159843 and b > 1.

Examples

			21463407 = 271^3 + 116^3 = 284^3 - 113^3 = 368^3 - 305^3, and 271 & 116 are coprime, etc., so 21463407 is in the sequence.
		

Links

• Rosalie Fay, Table of n, a(n) for n = 1..165

Crossrefs

Cf. A023050 (positive cubes); A293650 (allows noncoprime); A293646, A293648