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 A247953 Numbers n such that 2^n + 33 is prime. 4
 2, 3, 6, 11, 12, 14, 15, 20, 30, 60, 68, 75, 108, 116, 135, 206, 210, 410, 446, 558, 851, 1482, 1499, 2039, 2051, 4196, 7046, 7155, 8735, 10619, 18420, 20039, 46719, 75348, 179790, 203018, 434246 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Some terms correspond to probable primes. Lifchitz link shows the terms 179790 found by Donovan Johnson and 203018 by Lelio R Paula. - Jens Kruse Andersen, Sep 30 2014 a(38) > 5*10^5. - Robert Price, Nov 07 2015 LINKS Henri & Renaud Lifchitz, PRP Records, search for 2^n+33 MAPLE A247957:=n->`if`(isprime(2^n+33), n, NULL): seq(A247957(n), n=0..1000); # Wesley Ivan Hurt, Sep 28 2014 MATHEMATICA Select[Range[10000], PrimeQ[2^# + 33] &] PROG (MAGMA) /* The code gives only the terms up to 851: */ [n: n in [1..1400]| IsPrime( 2^n + 33 )]; (PARI) is(n)=ispseudoprime(2^n+33) \\ Charles R Greathouse IV, Feb 20 2017 CROSSREFS Cf. similar sequences listed in A247952. Sequence in context: A296444 A038752 A125714 * A284091 A004038 A152038 Adjacent sequences:  A247950 A247951 A247952 * A247954 A247955 A247956 KEYWORD nonn,more AUTHOR Vincenzo Librandi, Sep 28 2014 EXTENSIONS a(30)-a(34) from Jens Kruse Andersen, Sep 30 2014 a(35)-a(36) (discovered by Donovan Johnson and Lelio R Paula, respectively; see the Lifchitz link) added by Robert Price, Oct 04 2015 a(37) from Robert Price, Nov 07 2015 STATUS approved

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Last modified June 25 10:29 EDT 2019. Contains 324351 sequences. (Running on oeis4.)