A030724 Numbers k such that A030717(k) = 2.

3, 4, 7, 21, 26, 27, 33, 34, 40, 47, 55, 65, 82, 83, 95, 96, 111, 112, 114, 129, 130, 132, 138, 150, 152, 159, 175, 199, 200, 227, 229, 239, 255, 258, 259, 260, 270, 271, 288, 291, 293, 303, 304, 324, 329, 339, 340, 345, 377, 378

Offset: 1

Author

Clark Kimberling

Keywords

• nonn

Links

• Seiichi Manyama, Table of n, a(n) for n = 1..10000
• Michael De Vlieger, Plot a(s(j) + k - 1) at (j,k) for j = 1..512 and s = partial sums of A030719, showing a(m) = 2 in red and a(m) != 2 in light blue.

Crossrefs

Cf. A030723, A030725, A030726.

Cf. A030717.

Programs

Mathematica

nn = 30; m = 2; c[] = 0; k = a[1] = c[1] = 1; Reap[Do[w = Union@ Array[a, k]; Do[Set[a[j + k], c[w[[j]]]]; If[a[j + k] == m, Sow[m]], {j, Length[w]}]; Do[c[a[j + k]]++, {j, Length[w]}]; k += Length[w], {n, nn}] ][[-1, -1]] (* _Michael De Vlieger, Nov 19 2022 *)