A167132 Gaps between twin prime pairs.

0, 4, 4, 10, 10, 16, 10, 28, 4, 28, 10, 28, 10, 4, 28, 10, 28, 10, 28, 34, 70, 10, 28, 58, 46, 28, 16, 22, 16, 148, 10, 4, 28, 22, 136, 10, 16, 10, 28, 58, 76, 46, 10, 10, 16, 106, 22, 28, 4, 118, 10, 46, 28, 22, 64, 82, 4, 52, 16, 46, 28, 52, 4, 22, 16, 10, 94, 28, 40, 28, 40, 166

Offset: 1

Author

Oleg Zyakun, Oct 28 2009

Keywords

• nonn

Comments

Let G_n denote the twins gap between two consecutive twins, thus a twins gap is the difference between two consecutive twins (p_n, p_n+2) and (p_m, p_m+2), i.e., the difference between p_m and p_n+2. G_n = p_m - (p_n +2) We have: G_1 = 0, G_2 = 4, G_3 = 4, G_4 = 10.

Links

• T. D. Noe, Table of n, a(n) for n = 1..10000
• Program to generate the sequence

Programs

Maple

A001359 := proc(n) if n = 1 then 3; else a := nextprime(procname(n-1)) ; while not isprime(a+2) do a := nextprime(a) ; od: return a; fi; end: A006512 := proc(n) A001359(n)+2 ; end: A167132 := proc(n) A001359(n+1)-A006512(n) ; end: seq(A167132(n),n=1..120) ; # R. J. Mathar, Oct 29 2009

Mathematica

ps = Prime[Range[1000]]; p2 = Flatten[Position[Differences[ps], 2]]; Differences[ps[[p2]]] - 2 (* T. D. Noe, Jan 10 2012 *)

Formula

a(n) = A001359(n+1) - A006512(n). - R. J. Mathar, Oct 29 2009