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 A057197 Numbers n such that 2^n + 15 is prime. 14
 1, 2, 3, 4, 5, 6, 8, 10, 11, 12, 15, 16, 22, 23, 26, 30, 32, 40, 42, 46, 61, 72, 76, 155, 180, 198, 203, 310, 328, 342, 508, 510, 515, 546, 808, 1563, 2772, 3882, 3940, 4840, 7518, 11118, 11552, 11733, 12738, 12858, 17421, 44122, 64660, 163560, 172455, 180496, 325866, 481840 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(55) > 5*10^5. - Robert Price, Sep 14 2015 For these numbers n, 2^(n-1)*(2^n+15) has deficiency 16, cf. A125248. - M. F. Hasler, Jul 18 2016 LINKS H. Lifchitz & R. Lifchitz (Editors), PRP Top Records, of the form 2^n+15. MATHEMATICA Do[ If[ PrimeQ[ 2^n + 15 ], Print[n]], { n, 1, 12422 }] Select[Range[15000], PrimeQ[2^# + 15] &] (* Vincenzo Librandi, Aug 28 2015 *) PROG (MAGMA) [n: n in [0..1500] | IsPrime(2^n+15)]; // Vincenzo Librandi, Aug 28 2015 (PARI) for(n=1, 9e9, ispseudoprime(2^n+15)&&print1(n", ")) \\ M. F. Hasler, Jul 18 2016 CROSSREFS Cf. A059242, A057732, A019434, A057195. Sequence in context: A088232 A070994 A291686 * A067936 A087721 A226244 Adjacent sequences:  A057194 A057195 A057196 * A057198 A057199 A057200 KEYWORD nonn AUTHOR Robert G. Wilson v, Sep 15 2000 EXTENSIONS a(45)-a(53) from Robert Price, Dec 06 2013 a(54) from Robert Price, Sep 14 2015 STATUS approved

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Last modified May 7 15:45 EDT 2021. Contains 343651 sequences. (Running on oeis4.)