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A128661
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).
5
3, 7, 14, 15, 21, 32, 34, 47, 67, 69, 174, 369, 568, 3193, 3882, 5426
OFFSET
1,1
MATHEMATICA
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 *)
KEYWORD
nonn,more
AUTHOR
Pierre CAMI, Mar 19 2007
EXTENSIONS
a(14)-a(16) from Michael S. Branicky, Jul 22 2023
STATUS
approved