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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
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
Sequence in context: A258677 A184382 A126771 * A224623 A210331 A233690
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 June 25 13:13 EDT 2024. Contains 373705 sequences. (Running on oeis4.)