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Primes of the form p*q*r-2, where p, q and r are distinct primes.
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%I #12 Mar 21 2013 06:54:50

%S 103,163,193,229,271,283,383,397,433,463,593,607,613,643,661,739,757,

%T 859,883,967,1013,1021,1063,1093,1103,1129,1171,1237,1279,1307,1433,

%U 1453,1489,1493,1531,1543,1549,1579,1597,1613,1657,1693,1741,1747,1831

%N Primes of the form p*q*r-2, where p, q and r are distinct primes.

%H Vincenzo Librandi, <a href="/A115267/b115267.txt">Table of n, a(n) for n = 1..1000</a>

%F {A007304(n)-2} INTERSECTION {A000040}. - _Jonathan Vos Post_, Mar 06 2006

%e 103 = 3*5*7-2, 163 = 3*5*11-2 etc.

%t Select[Prime[Range[400]],Length[FactorInteger[ #+2]]==Plus@@(Last/@FactorInteger[ #+2])==3&]

%Y Cf. A115093 Primes of the form p*q-2, where p and q are distinct primes.

%Y Cf. A000040, A001359, A007304, A115093.

%K nonn

%O 1,1

%A _Zak Seidov_, Mar 04 2006