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Primes p such that p+2 is the square of a product of 3 distinct primes.
3

%I #7 Feb 17 2016 02:54:26

%S 53359,74527,81223,127447,159199,184039,189223,314719,354023,370879,

%T 378223,416023,439567,511223,804607,974167,1046527,1092023,1177223,

%U 1238767,1535119,1600223,1718719,2059223,2082247,2140367,2223079

%N Primes p such that p+2 is the square of a product of 3 distinct primes.

%C Primes of the form A162143(k)-2.

%H Chai Wah Wu, <a href="/A164519/b164519.txt">Table of n, a(n) for n = 1..11612</a>

%e 53359 + 2 = 3^2*7^2*11^2. 74527 + 2 = 3^2*7^2*13^2.

%t f[n_]:=FactorInteger[n][[1,2]]==2&&Length[FactorInteger[n]]==3&&FactorInteger[n][[2, 2]]==2&&FactorInteger[n][[3,2]]==2; lst={};Do[p=Prime[n];If[f[p+2], AppendTo[lst,p]],{n,4,9!}];lst

%Y Cf. A056899, A164517, A164518

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Aug 14 2009

%E Definition rephrased by _R. J. Mathar_, Oct 21 2009