A114227 Smallest odd prime q such that 2q + prime(n) is prime.

3, 3, 3, 3, 3, 5, 3, 7, 3, 3, 3, 5, 3, 3, 7, 3, 3, 13, 3, 5, 3, 7, 3, 3, 3, 3, 11, 7, 5, 3, 7, 5, 7, 3, 3, 5, 3, 3, 7, 5, 3, 3, 7, 17, 11, 3, 3, 5, 3, 19, 5, 3, 3, 3, 7, 3, 3, 13, 5, 7, 3, 3, 17, 7, 3, 5, 3, 5, 3, 7, 3, 3, 5, 3, 37, 11, 19, 5, 7, 5, 13, 3, 5, 3, 7, 3, 3, 23, 37, 31, 11, 43, 5, 3, 7, 13, 17

Offset: 3

Author

Lei Zhou, Nov 18 2005

Keywords

• easy
• nonn

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 3..10000

Crossrefs

Cf. A000040, A010051, A114228.

Programs

Haskell

a114227 n = head [p | p <- tail a000040_list,
                      a010051' (2 * p + a000040 n) == 1]
-- Reinhard Zumkeller, Oct 29 2013

Mathematica

Table[p1 = Prime[n1]; n2 = 2; p2 = 3; While[ cp = p1 + 2*p2; ! PrimeQ[cp], n2++; p2 = Prime[n2]]; p2, {n1, 3, 202}]