A078387 Moebius's mu of numbers which can be written as sum of a positive square and a positive cube.

-1, -1, 0, 1, 0, -1, 0, 1, 0, -1, 1, 0, -1, -1, 0, 0, 0, 1, 0, 1, 0, 0, -1, 0, 0, 1, -1, 1, 0, -1, 0, -1, 1, 0, -1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, -1, 0, -1, 1, 1, 0, 0, -1, 0, 1, 0, 1, 0, -1, 0, 1, 0, -1, -1, -1, 0, -1, 0, 0, 1, -1, 0, -1, 0, -1, 0, 0, 0, 0, 1, 0, 0, -1, 0, -1, 0, 0, 0, -1, -1, 0, 1, 0, 0, -1, 1, -1

Offset

1,1

Links

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

Formula

a(n) = A008683(A055394(n)).

Mathematica

MoebiusMu[Select[Range[200], Length[Reduce[a^2 + b^3 == # && a > 0 && b > 0, {a, b}, Integers]] > 0 &]] (* Amiram Eldar, Mar 27 2025 *)

Crossrefs

Cf. A008683, A055394, A078386.

Sequence in context: A135528 A163805 A267015 * A189292 A331168 A331281

Adjacent sequences: A078384 A078385 A078386 * A078388 A078389 A078390

Keyword

sign

Author

Reinhard Zumkeller, Nov 25 2002

Status

approved