A066650 Numbers not of the form a^2 + b^3 with a, b > 0.

1, 3, 4, 6, 7, 8, 11, 13, 14, 15, 16, 18, 19, 20, 21, 22, 23, 25, 27, 29, 30, 32, 34, 35, 38, 39, 40, 41, 42, 45, 46, 47, 48, 49, 51, 53, 54, 55, 56, 58, 59, 60, 61, 62, 64, 66, 67, 69, 70, 71, 74, 75, 77, 78, 79, 81, 83, 84, 85, 86, 87, 88, 90, 92, 93, 94, 95, 96, 97, 98, 99

Offset: 1

Author

Reinhard Zumkeller, Dec 17 2001

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A066649. Complement of A055394.

Programs

Mathematica

q[n_] := Length[Reduce[a^2 + b^3 == n && a > 0 && b > 0, {a, b}, Integers]] == 0; Select[Range[100], q] (* Amiram Eldar, Mar 20 2025 *)