A391798 Numbers k such that prime(2*k + 2) - prime(2*k) = prime(2*k + 1) - prime(2*k - 1).

2, 3, 5, 11, 13, 14, 15, 17, 19, 21, 22, 32, 36, 39, 41, 47, 52, 53, 63, 74, 75, 76, 77, 83, 86, 88, 91, 93, 96, 106, 118, 122, 124, 125, 128, 136, 137, 143, 151, 157, 173, 174, 175, 195, 199, 217, 219, 237, 238, 242, 259, 261, 280, 289, 290, 293, 296

Offset

1,1

Links

Table of n, a(n) for n=1..57.

Mathematica

z = 300; p[n_] := Prime[n];
a[n_] := p[2 n + 2] - p[2 n] - p[2 n + 1] + p[2 n - 1];
Select[Range[z], a[#] < 0 &]   (* A391797 *)
Select[Range[z], a[#] == 0 &]  (* A391798 *)
Select[Range[z], a[#] > 0 &]   (* A391799 *)

Crossrefs

Cf. A000027, A000040, A022884, A110854, A391797, A391799, A391800.

Sequence in context: A103027 A093902 A269004 * A379316 A100475 A187921

Adjacent sequences: A391795 A391796 A391797 * A391799 A391800 A391801

Keyword

nonn

Author

Clark Kimberling, Dec 23 2025

Status

approved