Position of odd numbers in the terms of the central hexanomial coefficients.
0, 1, 3, 7, 11, 15, 19, 23, 27, 31, 39, 47, 51, 55, 59, 63, 79, 91, 95, 103, 111, 115, 119, 123, 127, 155, 159, 179, 183, 187, 191, 207, 219, 223, 231, 239, 243, 247, 251, 255, 307, 311, 315, 319, 359, 367, 371, 375, 379, 383, 411, 415, 435, 439, 443, 447, 463
1
The differences of these terms have an interesting structure, which is shown in S000979.
T. D. Noe, Plot of 715 terms
T. D. Noe, Table of 715 terms
(Mma) prod = 1; t = Table[prod = Expand[prod*Sum[x^k, {k, 0, 5}]]; Max[CoefficientList[prod, x]], {n, 2^8}]; t = Join[{1}, t]; Flatten[Position[t, _?(OddQ[#] &)] ] - 1
Cf. A018901, S000977, S000979.
nonn
T. D. Noe, Mar 08 2017