login
A339995
Numbers that are the sum of an odd cube and a nonzero even cube.
0
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
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: A187554 A338010 A267702 * A085366 A304913 A173245
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Dec 25 2020
STATUS
approved