A339995 Numbers that are the sum of an odd cube and a nonzero even cube.

9, 35, 65, 91, 133, 189, 217, 243, 341, 351, 407, 513, 539, 559, 637, 737, 793, 855, 945, 1001, 1027, 1125, 1241, 1339, 1343, 1395, 1547, 1729, 1755, 1843, 1853, 2071, 2205, 2261, 2331, 2413, 2457, 2709, 2745, 2771, 2869, 3059, 3087, 3197, 3383, 3439, 3473, 3591, 3887, 3925

Offset

1,1

Links

Table of n, a(n) for n=1..50.

Example

35 is in the sequence since 2^3 + 3^3 = 8 + 27 = 35, where 8 is a nonzero even cube and 27 is an odd cube.

Mathematica

Table[If[Sum[Sign[Mod[i, 2] Mod[n - i + 1, 2] + Mod[i + 1, 2] Mod[n - i, 2]] (Floor[i^(1/3)] - Floor[(i - 1)^(1/3)]) (Floor[(n - i)^(1/3)] - Floor[(n - i - 1)^(1/3)]), {i, Floor[n/2]}] > 0, n, {}], {n, 1200}] // Flatten

Crossrefs

Cf. A010057.

Sequence in context: A379128 A338010 A267702 * A085366 A304913 A173245

Adjacent sequences: A339992 A339993 A339994 * A339996 A339997 A339998

Keyword

nonn

Author

Wesley Ivan Hurt, Dec 25 2020

Status

approved