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Primes p of the form 6n-1 such that p-1 is a semiprime and p+2 is prime or prime squared.
6

%I #11 Jul 01 2022 11:07:44

%S 5,11,23,47,59,107,167,179,227,347,359,839,1019,1319,1367,1487,1619,

%T 2027,2207,2999,3119,3167,3467,4127,4259,4547,4787,4799,5099,5639,

%U 5879,6659,6779,6827,7559,8819,10007,10607,11699,12107,12539,14387,14867,15287,15647

%N Primes p of the form 6n-1 such that p-1 is a semiprime and p+2 is prime or prime squared.

%C Except term 7, same as A181602.

%t Select[6*Range[3000]-1,PrimeQ[#]&&PrimeOmega[#-1]==2&&AnyTrue[ {#+2,Sqrt[ #+2]},PrimeQ]&] (* _Harvey P. Dale_, Jul 01 2022 *)

%K nonn

%O 1,1

%A _Giovanni Teofilatto_, Nov 18 2010