A191473 Let a(1) = 3. For n > 1, a(n) is the smallest prime p > a(n-1) such that q = (a(n-1) + p)/4 is prime.

3, 5, 7, 13, 31, 37, 79, 109, 127, 157, 199, 229, 367, 397, 607, 661, 727, 829, 967, 997, 1039, 1213, 1399, 1693, 1759, 1789, 1999, 2053, 2143, 2221, 2383, 2389, 2503, 3229, 3319, 3469, 3823, 4093, 4159, 4357, 4591, 4597, 4639, 4789, 4903, 4933, 5431, 5581

Offset: 1

Author

Zak Seidov, Aug 27 2012

Keywords

• nonn

Comments

Corresponding values of q: 2, 3, 5, 11, 17, 29, 47, 59, 71, 89, 107.

Links

• Zak Seidov, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A126938.

Programs

Mathematica

p=3; s={p}; Do[q=Prime[n]; If[PrimeQ[(p+q)/4], AppendTo[s,q]; p=q], {n, 3, 1000}]; s
nxt[n_]:=Module[{p=NextPrime[n]},While[!PrimeQ[(n+p)/4],p=NextPrime[ p]]; p]; NestList[nxt,3,50] (* Harvey P. Dale, Nov 25 2013 *)