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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

Table of n, a(n) for n=1..54.

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.)