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

Author

Clark Kimberling, Oct 03 2014

Keywords

• nonn
• easy

Examples

			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,...)
		

Links

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

Crossrefs

Cf. A248180, A248196.

Programs

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 *)