A248561 Numbers k such that A248559(k+1) = A248559(k) + 2.

4, 7, 9, 12, 14, 16, 18, 20, 22, 24, 26, 27, 29, 31, 33, 35, 37, 39, 40, 42, 44, 46, 48, 49, 51, 53, 55, 57, 58, 60, 62, 64, 66, 67, 69, 71, 73, 74, 76, 78, 80, 81, 83, 85, 87, 89, 90, 92, 94, 96, 97, 99, 101, 103, 104, 106, 108, 110, 111, 113, 115, 117, 118

Offset

1,1

Links

Clark Kimberling, Table of n, a(n) for n = 1..500

Example

(A248559(k+1) - A248559(k)) = (1, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2,...), so that A248561 = (1, 2, 3, 5, 6, 8, 10, 11, 13, ...) and A248562 = (4, 7, 9, 12, 14, 16, 18, 20, ...).

Mathematica

z = 200; p[k_] := p[k] = Sum[1/(h*2^h), {h, 1, k}]
N[Table[Log[2] - p[n], {n, 1, z/5}]]
f[n_] := f[n] = Select[Range[z], Log[2] - p[#] < 1/3^n &, 1]
u = Flatten[Table[f[n], {n, 1, z}]]    (* A248559 *)
Flatten[Position[Differences[u], 1]]   (* A248560 *)
Flatten[Position[Differences[u], 2]]   (* A248561 *)

Crossrefs

Cf. A248559, A248560.

Sequence in context: A085922 A048973 A092861 * A360925 A007072 A186323

Adjacent sequences: A248558 A248559 A248560 * A248562 A248563 A248564

Keyword

nonn,easy

Author

Clark Kimberling, Oct 09 2014

Status

approved