A296117 Base-2 pseudoprimes of the form 2*p*q where p and q are primes.

161038, 49699666, 760569694, 4338249646, 357647681422, 547551530002, 3299605275646, 22999986587854, 42820164121582, 55173914702146, 69345154539266, 353190859033982

Offset: 1

Author

Max Alekseyev, Dec 05 2017

Keywords

• nonn
• more

Comments

a(5) and a(10) are found by McDaniel (1989).

Terms in this sequence are of the form 2pq where p and q are distinct odd primes (A075819). - Charles R Greathouse IV, Dec 05 2017

Links

• W. L. McDaniel, Some pseudoprimes and related numbers having special forms, Math. Comp. 53:187 (1989), 407-409.

Crossrefs

Subsequence of A006935 and hence of A015919.

The even terms of A215672.

Intersection of A006935 and A215672. - Felix Fröhlich, Dec 05 2017

Cf. A270973, A075819, A001220.

Programs

PARI

list(lim)=my(v=List(),pq); forprime(p=3,lim\6, forprime(q=3,min(lim\(2*p),p), pq=p*q; if(Mod(4,pq)^pq==2, listput(v,2*pq)))); Set(v) \\ Charles R Greathouse IV, Dec 05 2017