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 A259298 Numbers k such that k^2*2^k + 3 is prime. 0
 0, 1, 2, 11, 22, 40, 79, 145, 152, 244, 271, 1471, 2516, 3460, 4130, 4550, 7534, 12973, 14051, 14176, 16093, 16952 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Primes: 3, 5, 19, 247811, 2030043139, 1759218604441603,... LINKS EXAMPLE 2 is in this sequence because 2^2*2^2 + 3 = 19 and 19 is prime. MATHEMATICA Select[Range[0, 10000], PrimeQ[#^2 2^# + 3] &] (* Vincenzo Librandi, Jun 25 2015 *) PROG (MAGMA) [n: n in [0..1000] | IsPrime(n^2*2^n+3)]; (PARI) is(n)=ispseudoprime(n^2*2^n+3) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Cf. A058780. Sequence in context: A018590 A057531 A018661 * A018711 A018737 A162468 Adjacent sequences:  A259295 A259296 A259297 * A259299 A259300 A259301 KEYWORD nonn,more AUTHOR Juri-Stepan Gerasimov, Jun 23 2015 EXTENSIONS More terms from Vincenzo Librandi, Jun 25 2015 a(18)-a(22) from Jinyuan Wang, May 15 2020 STATUS approved

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Last modified August 16 05:55 EDT 2022. Contains 356160 sequences. (Running on oeis4.)