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A108272 Consider primes p and q such that p = 2^k + 21 and q = 2^(k+1) + 21 for some k; sequence gives values of p. 1
29, 37, 149, 32789, 2251799813685269 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No additional terms up to k = 2000. - Harvey P. Dale, May 12 2019

LINKS

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

MATHEMATICA

Select[Partition[2^Range[60]+21, 2, 1], AllTrue[#, PrimeQ]&][[All, 1]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, May 12 2019 *)

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. A108273.

Sequence in context: A304688 A167470 A152865 * A121999 A069530 A259032

Adjacent sequences:  A108269 A108270 A108271 * A108273 A108274 A108275

KEYWORD

nonn

AUTHOR

Cino Hilliard, Jun 29 2005

STATUS

approved

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Last modified September 19 23:31 EDT 2019. Contains 327207 sequences. (Running on oeis4.)