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Primorials P which have at least one prime neighbor; i.e., P+1 or P-1 or both are primes.
6

%I #20 Mar 17 2020 21:19:14

%S 1,2,6,30,210,2310,30030,200560490130,304250263527210,

%T 23768741896345550770650537601358310

%N Primorials P which have at least one prime neighbor; i.e., P+1 or P-1 or both are primes.

%C A supersequence of A088256.

%C Next term a(11) is 131 digits and is too large to include.

%H Alois P. Heinz, <a href="/A088257/b088257.txt">Table of n, a(n) for n = 1..19</a>

%t Select[FoldList[Times,1,Prime[Range[70]]],PrimeQ[#-1]||PrimeQ[#+1]&] (* _Harvey P. Dale_, Oct 22 2011 *)

%Y Cf. A002110, A088256.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Sep 27 2003

%E More terms from _Ray Chandler_, Sep 28 2003