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A154942
Primes p such that (p-1)*p*(p+1)-p-2 and (p-1)*p*(p+1)+p+2 are primes.
1
3, 5, 29, 71, 113, 263, 1103, 2339, 3203, 3413, 3593, 3659, 3719, 4421, 5939, 6269, 7841, 9011, 9029, 13121, 13841, 14423, 15671, 17033, 19073, 22079, 22811, 26783, 27851, 28949, 29303, 30839, 31973, 32063, 32141, 34301, 38543, 38873, 39119
OFFSET
1,1
COMMENTS
2*3*4=24-3-2=19, 2*3*4=24+3+2=29, ...
MATHEMATICA
lst={}; Do[p=Prime[n]; If[PrimeQ[(p-1)*p*(p+1)-p-2]&&PrimeQ[(p-1)*p*(p+1)+p+2], AppendTo[lst, p]], {n, 8!}]; lst
prQ[n_]:=Module[{x=n^3-n, y=n+2}, And@@PrimeQ[{x+y, x-y}]]; Select[Prime[ Range[4200]], prQ] (* Harvey P. Dale, Jun 21 2012 *)
KEYWORD
nonn
AUTHOR
STATUS
approved