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A103875 Numbers k such that 2*P(k) + 5, 2*P(k+1) + 7, 2*P(k+2) + 9, 2*P(k+3) + 11 are also consecutive primes where P(i) = i-th prime. 2
43465, 79433, 82148, 300879, 584423, 609169, 631181, 704593, 1293377, 1393266, 1939691, 2203731, 2396444, 2585471, 3224519, 3533876, 3687348, 3951399, 4094469, 4239250, 4442048, 4648592, 4744723, 5076823, 5190219, 5397694, 6779299, 7850072, 7942431, 8679283, 8851519 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..31.

MATHEMATICA

cpQ[n_]:=Module[{p=Prime[n], a, b, c, d}, a=2p+5; b=2Prime[n+1]+7; c= 2*Prime[n+2]+9; d=2Prime[n+3]+11; AllTrue[{a, b, c, d}, PrimeQ]&&b== NextPrime[a]&&c==NextPrime[b]&&d==NextPrime[c]]; Select[Range[10^6], cpQ] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 14 2017 *)

PROG

(PARI) lista(nn) = {my(k=1, v=[2, 3, 5, 7]); forprime(p=11, nn, k++; v=concat(v[2..4], p); if(ispseudoprime(2*v[1]+5) && nextprime(2*v[1]+6)==2*v[2]+7 && nextprime(2*v[2]+8)==2*v[3]+9 && nextprime(2*v[3]+10)==2*v[4]+11, print1(k, ", "))); } \\ Jinyuan Wang, Mar 05 2020

CROSSREFS

Cf. A103873, A103874.

Sequence in context: A258677 A184382 A126771 * A224623 A210331 A233690

Adjacent sequences:  A103872 A103873 A103874 * A103876 A103877 A103878

KEYWORD

nonn

AUTHOR

Pierre CAMI, Feb 19 2005

EXTENSIONS

Corrected and extended by Harvey P. Dale, Jan 14 2017

More terms from Jinyuan Wang, Mar 05 2020

STATUS

approved

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Last modified August 8 11:31 EDT 2020. Contains 336298 sequences. (Running on oeis4.)