A083562 - OEIS

%I #11 Sep 29 2019 03:10:30

%S 3,3,3,17,3,5,67,29,3,3,3,373,5,3,5,3,257,641,7,383,43,139,571,3967,

%T 2971,7,677,3,317,571,71,659,11,43,59,479,719,2293,5,5237,1039,37,757,

%U 719,41,5023,3,31,971,7,593,163,5003,1867,19,1283,4549,17,4817,1301

%N Beginning of first chain of n consecutive primes whose product + 2 is prime.

%H Amiram Eldar, <a href="/A083562/b083562.txt">Table of n, a(n) for n = 1..500</a>

%e 17 is the smallest prime in 17, 19, 23, 29 which is the first chain of four consecutive primes whose product + 2 is prime: 17 * 19 * 23 * 29 + 2 = 215443 (prime). Hence a(4) = 17.

%t pl=Prime[Range[1000]]; frp[n_] := Module[{pl2=Partition[pl, n, 1]}, First[Select[pl2, PrimeQ[(Times@@#)+2]&][[1]]]]; Table[frp[i], {i, 25}]

%K nonn

%O 1,1

%A _Joseph L. Pe_, Jun 12 2003

%E More terms from _Amiram Eldar_, Sep 29 2019