A129928 Primes equal to 3*Sp - 2, where Sp is a semiprime.

43, 61, 73, 97, 103, 151, 163, 193, 229, 271, 277, 283, 331, 367, 397, 421, 433, 463, 547, 601, 607, 613, 643, 661, 709, 739, 757, 859, 883, 907, 967, 1021, 1063, 1093, 1129, 1171, 1231, 1237, 1249, 1279, 1453, 1489, 1531, 1543, 1549, 1579, 1597, 1609

Offset

1,1

Links

Table of n, a(n) for n=1..48.

Formula

a(n) = 3*A129926(n)-2. [R. J. Mathar, Apr 22 2010]

Mathematica

3*Select[Range[600], PrimeOmega[#]==2&&PrimeQ[3#-2]&]-2 (* James C. McMahon, Feb 02 2025 *)

Crossrefs

Sequence in context: A064508 A102540 A063641 * A317393 A253848 A245742

Adjacent sequences: A129925 A129926 A129927 * A129929 A129930 A129931

Keyword

nonn,changed

Author

Giovanni Teofilatto, Jun 06 2007

Extensions

Extended by R. J. Mathar, Apr 22 2010

Status

approved