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%I #13 Dec 25 2022 14:04:11
%S 1237,1493,1549,1597,2137,2753,2767,2917,3533,3617,4013,4253,4919,
%T 5557,5683,5693,5783,6151,6353,6367,6917,6967,6983,7057,7187,7537,
%U 7687,7703,7883,8101,8167,8243,8447,8699,8731,8963,9697,9739,9787,9833,9887,10151
%N Primes p such that both p+2 and p-2 are products of 3 distinct primes.
%C None of the 3 distinct primes may have an exponent other than 1. - _Harvey P. Dale_, Dec 25 2022
%H Chai Wah Wu, <a href="/A161868/b161868.txt">Table of n, a(n) for n = 1..10000</a>
%e 1237-2=5*13*19. 1237+2=3*7*59. 1493-2=3*7*71. 1493+2=5*13*23.
%t fQ[n_]:=Last/@FactorInteger[n]=={1,1,1};q=2;lst={};Do[p=Prime[n];If[fQ[p-q]&&fQ[p+q], AppendTo[lst,p]],{n,7!}];lst
%t Select[Prime[Range[1250]],FactorInteger[#+2][[All,2]]== FactorInteger[ #-2] [[All,2]]=={1,1,1}&] (* _Harvey P. Dale_, Aug 03 2016 *)
%t Select[Prime[Range[1250]],PrimeNu[#+{2,-2}]==PrimeOmega[#+{2,-2}] == {3,3}&] (* _Harvey P. Dale_, Dec 25 2022 *)
%Y Cf. A007304. [_R. J. Mathar_, Jun 23 2009]
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Jun 20 2009
%E Definition rephrased by _R. J. Mathar_, Jun 23 2009
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