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A244916
Primes prime(i) such that prime(i) + 2^(i+1) is also prime.
1
3, 31, 71, 97, 107, 277, 307, 641, 907, 967, 1009, 1447, 3463, 3527, 7757, 8167, 250867, 279047
OFFSET
1,1
MAPLE
for i from 1 do
p := ithprime(i) ;
if isprime(p+2^(i+1)) then
printf("%d, \n", p) ;
end if;
end do: # R. J. Mathar, Jul 12 2014
MATHEMATICA
p = 2; lst = {}; While[p < 900000, If[ PrimeQ[ 2^(PrimePi@ p +1) + p], AppendTo[lst, p]; Print@ p]; p = NextPrime@ p]; lst
PROG
(PARI) lista(nn) = {ip = 1; forprime(p=2, nn, if (isprime(2^(ip+1)+p), print1(p, ", ")); ip++; ); } \\ Michel Marcus, Jul 12 2014
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
Robert G. Wilson v, Jul 09 2014
STATUS
approved