A108273 Consider primes p and q such that p = 2^k + 21 and q = 2^(k+1) + 21 for some k; sequence gives values of q.

37, 53, 277, 65557, 4503599627370517

Offset

1,1

Links

Table of n, a(n) for n=1..5.

Mathematica

Select[Partition[2^Range[100]+21, 2, 1], AllTrue[#, PrimeQ]&][[All, 2]] (* Harvey P. Dale, Jan 17 2021 *)

Prog

(PARI) g(m, n, b) = { for(x=0, n, y=m+b^x+b%2; z=m+b^(x+1)+b%2; if(isprime(y)&isprime(z), print1(y", ") ) ) }

Crossrefs

Cf. A108272.

Sequence in context: A242930 A139918 A289510 * A045223 A134222 A179150

Adjacent sequences: A108270 A108271 A108272 * A108274 A108275 A108276

Keyword

nonn

Author

Cino Hilliard, Jun 29 2005

Status

approved