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Numbers k such that p(k+1)# + p(k)# - p(k-1)# - 1 is prime where p(i)# = product of first i primes = A002110(i).
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%I #10 Jul 23 2023 01:48:13

%S 3,7,14,15,21,32,34,47,67,69,174,369,568,3193,3882,5426

%N Numbers k such that p(k+1)# + p(k)# - p(k-1)# - 1 is prime where p(i)# = product of first i primes = A002110(i).

%t Flatten[Position[Partition[Rest[FoldList[Times,1,Prime[Range[ 600]]]],3,1], _?(PrimeQ[#[[3]]+#[[2]]-#[[1]]-1]&),{1},Heads-> False]]+1 (* _Harvey P. Dale_, May 26 2013 *)

%Y Cf. A002110, A128420, A128421, A128657, A128658, A128659, A128660, A128662.

%K nonn,more

%O 1,1

%A _Pierre CAMI_, Mar 19 2007

%E a(14)-a(16) from _Michael S. Branicky_, Jul 22 2023