A190354 Primes p such that p,q,r,s are consecutive primes and 2p+9, 2q+9, 2r+9, 2s+9 are also primes.

887, 907, 4211, 6569, 8447, 23339, 23357, 30809, 33427, 33937, 38839, 57529, 57557, 57859, 70271, 77621, 77641, 77647, 77659, 80747, 86587, 87691, 109537, 115769, 116041, 117251, 160681, 192781, 207797, 217387, 228257, 228281, 232457, 244339

Offset

1,1

Comments

The smallest in a group of four consecutive primes in A023207. - R. J. Mathar, Jun 02 2011

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Maple

isA023207 := proc(n) isprime(n) and isprime(2*n+9) ; end proc:
isA190354 := proc(n) local q, r, s ; if isprime(n) then q := nextprime(n) ; r := nextprime(q) ; s := nextprime(r) ; isA023207(n) and isA023207(q) and isA023207(r) and isA023207(s) ; else return false; end if; end proc:
for i from 1 do p := ithprime(i) ; if isA190354(p) then print(p) ; end if; end do: # R. J. Mathar, Jun 02 2011

Mathematica

p2Q[n_]:=And@@PrimeQ[2#+9&/@n]; Transpose[Select[Partition[Prime[ Range[22000]], 4, 1], p2Q]][[1]] (* Harvey P. Dale, Jun 10 2011 *)

Prog

(PARI) old(p, k)=while(k--, p=precprime(p-1)); p; k=0; forprime(p=2, 1e6, if(isprime(p+p+9), if(k++>3, print1(old(p, 4)", ")), k=0))

Crossrefs

Sequence in context: A031794 A020393 A103811 * A164513 A031938 A165504

Adjacent sequences: A190351 A190352 A190353 * A190355 A190356 A190357

Keyword

nonn

Author

Pierre CAMI, May 09 2011

Status

approved