A242260 Primes p such that p^2-2 is semiprime.

11, 17, 23, 31, 41, 53, 67, 73, 79, 83, 97, 109, 113, 149, 151, 163, 167, 197, 199, 229, 241, 251, 269, 281, 307, 331, 349, 379, 383, 389, 401, 433, 439, 457, 461, 463, 503, 547, 563, 593, 599, 601, 613, 617, 631, 643, 659, 661, 673, 691, 701, 709, 739, 769

Offset: 1

Author

Zak Seidov, May 09 2014

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Subsequence of A219602. Cf. A001358.

Programs

Maple

filter:= t -> isprime(t) and numtheory:-bigomega(t^2-2)=2:
select(filter, [seq(i,i=3..10000,2)]); # Robert Israel, Nov 17 2019

Mathematica

Select[Table[Prime[k], {k, 1000}], PrimeOmega[#^2 - 2] == 2 &] (* M7*)

PARI

s=[]; forprime(p=2, 1000, if(bigomega(p^2-2)==2, s=concat(s, p))); s \\ Colin Barker, May 10 2014