|
%I #7 Jul 23 2021 05:30:34
%S 20382,409331,588060,718919,892113,1583347,1680668,2909044,4104093,
%T 4335628,4589071,4910417,5167262,5227231,5276556,5667695,6228570,
%U 7874791,8307560,8923874,9004943,9098100,9616214,9792649,10374603,12293364,12884611,13450210,13798661,13877345
%N Numbers k such that 2*prime(k)+1, 2*prime(k+1)+1, 2*prime(k+2)+3 and 2*prime(k+3)-3 are also consecutive primes.
%t s={}; n=1; p1=2; p2=3; p3=5; Do[p4 = NextPrime[p3]; If[PrimeQ[2*p1+1] && (np = NextPrime[2*p1+1]) == 2*p2+1 && (np2 = NextPrime[np]) == 2*p3+3 && NextPrime[np2] == 2*p4-3, AppendTo[s, n]]; p1=p2; p2=p3; p3=p4; n++, {10^5}]; s (* _Amiram Eldar_, Jul 23 2021 *)
%Y Cf. A103911, A103913.
%K nonn
%O 1,1
%A _Pierre CAMI_, Feb 21 2005
%E More terms from _Amiram Eldar_, Jul 23 2021
|
