A248612 Numbers k such that A248610(k+1) = A248610(k) + 1.

2, 4, 6, 7, 9, 10, 12, 13, 15, 16, 17, 19, 20, 21, 23, 24, 25, 27, 28, 29, 31, 32, 33, 35, 36, 37, 39, 40, 41, 43, 44, 45, 46, 48, 49, 50, 52, 53, 54, 56, 57, 58, 59, 61, 62, 63, 65, 66, 67, 68, 70, 71, 72, 74, 75, 76, 77, 79, 80, 81, 83, 84, 85, 86, 88, 89

Offset: 1

Author

Clark Kimberling, Oct 10 2014

Keywords

• nonn
• easy

Examples

			(A248610(k+1) - A248610(k)) = (0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, ...), so that A248611 = (1, 3, 5, 8, 11, 14, 18, 22, 26, ..) and A248612 = (2, 4, 6, 7, 9, 10, 12, 13, ...).
		

Links

• Clark Kimberling, Table of n, a(n) for n = 1..1500

Crossrefs

Cf. A248610, A248611, A248608.

Programs

Mathematica

z = 300; p[k_] := p[k] = Sum[1/((h^2)*Binomial[2 h, h]), {h, 1, k}]
d = N[Table[Pi^2/18 - p[k], {k, 1, z/5}], 12]
f[n_] := f[n] = Select[Range[z], Pi^2/18 - p[#] < 1/3^n &, 1]
u = Flatten[Table[f[n], {n, 1, z}]]  (* A248610 *)
d = Differences[u]
v = Flatten[Position[d, 0]]  (* A248611 *)
w = Flatten[Position[d, 1]]  (* A248612 *)