A066648 Cubes of the form a^2 + b^3 with a, b > 0.

512, 1000, 2744, 21952, 32768, 35937, 64000, 175616, 185193, 274625, 357911, 373248, 405224, 474552, 729000, 1157625, 1404928, 1481544, 2000376, 2097152, 2197000, 2299968, 2744000, 3241792, 3652264, 3723875, 4096000, 5451776, 7189057, 8000000, 10218313, 10360232

Offset: 1

Author

Reinhard Zumkeller, Dec 17 2001

Keywords

• nonn

Examples

			8^3 = a(0) = 512 = 169 + 343 = 13^2 + 7^3;
10^3 = a(1) = 1000 = 784 + 216 = 28^2 + 6^3.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..5000

Crossrefs

Cf. A055394, A066647, A228946.

Programs

Mathematica

q[n_] := Length[Reduce[a^2 + b^3 == n && a > 0 && b > 0, {a, b}, Integers]] > 0; Select[Range[220]^3, q] (* Amiram Eldar, Mar 20 2025 *)

Formula

a(n) = A228946(n)^3. - R. J. Mathar, Dec 03 2015