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 A175172 Primes p such that 3*2^p+1 is also prime. 2
 2, 5, 41, 353 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS FORMULA A000040 INTERSECT A002253. - R. J. Mathar, Jan 04 2011 EXAMPLE For p=2, 3*2^2+1=13; p=5. 3*2^5+1=97; p=41, 3*2^41+1=6597069766657. MAPLE select(p->isprime(p) and isprime(3*2^p+1), [\$0..5000]); # Muniru A Asiru, Dec 19 2018 MATHEMATICA Select[Prime[Range[1000]], PrimeQ[3 2^# + 1] &] (* Vincenzo Librandi, Dec 19 2018 *) PROG (MAGMA) [p: p in PrimesUpTo(4000) | IsPrime(3*2^p+1)] CROSSREFS Cf. A000040, A002253. Sequence in context: A185052 A088547 A009457 * A218057 A126469 A054859 Adjacent sequences:  A175169 A175170 A175171 * A175173 A175174 A175175 KEYWORD nonn,more AUTHOR Vincenzo Librandi, Mar 09 2010 STATUS approved

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Last modified May 5 23:41 EDT 2021. Contains 343579 sequences. (Running on oeis4.)