A115267 Primes of the form p*q*r-2, where p, q and r are distinct primes.

103, 163, 193, 229, 271, 283, 383, 397, 433, 463, 593, 607, 613, 643, 661, 739, 757, 859, 883, 967, 1013, 1021, 1063, 1093, 1103, 1129, 1171, 1237, 1279, 1307, 1433, 1453, 1489, 1493, 1531, 1543, 1549, 1579, 1597, 1613, 1657, 1693, 1741, 1747, 1831

Offset: 1

Author

Zak Seidov, Mar 04 2006

Keywords

• nonn

Examples

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

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Crossrefs

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

Cf. A000040, A001359, A007304, A115093.

Programs

Mathematica

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

Formula

{A007304(n)-2} INTERSECTION {A000040}. - Jonathan Vos Post, Mar 06 2006