A248195 Numbers k such that A248180(k+1) = A248180(k).

1, 2, 4, 6, 8, 10, 12, 14, 16, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 88, 90, 92, 94, 96, 98, 100, 102, 104, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124

Offset

0,2

Links

Clark Kimberling, Table of n, a(n) for n = 0..1500

Example

The difference sequence of A248180 is (0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1,...), so that A248195 = (1,2,4,6,8,10,12,14,16,19,...) and A248196 = (3,5,7,9,11,13,15,17,18,...)

Mathematica

$MaxExtraPrecision = Infinity;
z = 300; p[k_] := p[k] = Sum[1/Binomial[2 h + 1, h], {h, 0, k}] ;
r = Sum[1/Binomial[2 h + 1, h], {h, 0, Infinity}]  (* A248179 *)
r = 2/27 (9 + 2 Sqrt[3] \[Pi]); N[r, 20]
N[Table[r - p[n], {n, 0, z/10}]]
f[n_] := f[n] = Select[Range[z], r - p[#] < 1/2^n &, 1]
u = Flatten[Table[f[n], {n, 0, z}]]  (* A248180 *)
Flatten[Position[Differences[u], 0]] (* A248195 *)
Flatten[Position[Differences[u], 1]] (* A248196 *)

Crossrefs

Cf. A248180, A248196.

Sequence in context: A169921 A169919 A292512 * A094041 A058066 A249124

Adjacent sequences: A248192 A248193 A248194 * A248196 A248197 A248198

Keyword

nonn,easy

Author

Clark Kimberling, Oct 03 2014

Status

approved