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A188677 Primes p such that the minimum value of |p-2^x|, x>0, is also a prime. 1
11, 13, 19, 23, 29, 37, 43, 53, 59, 61, 67, 71, 83, 97, 109, 131, 139, 151, 157, 181, 197, 227, 233, 239, 251, 263, 269, 293, 317, 353, 359, 383, 409, 433, 439, 499, 509, 523, 541, 571, 601, 613, 619, 643, 661, 691, 709, 739, 751, 773, 797, 827, 857 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Originally submitted by Benoit Cloitre, Dec 17 2002 as A078686 and corrected by Robert G. Wilson v, Apr 08 2011.

LINKS

Table of n, a(n) for n=1..53.

FORMULA

Intersection of A086081 and A091932. - Robert G. Wilson v, May 27 2011

MATHEMATICA

fQ[n_] := Block[{x = Floor@ Log2@ n}, PrimeQ@ Min[n - 2^x, 2^(x+1) - n]]; Select[ Prime@ Range@ 150, fQ] (* Robert G. Wilson v, Apr 08 2011 *)

PROG

(PARI) is(n)=if(isprime(n), my(x=log(n)\log(2)); isprime(min(abs(n-1<<x), abs(n-2<<x))), 0) \\ Charles R Greathouse IV, Jan 10 2013

CROSSREFS

Cf. A078686, A086081, A091932.

Sequence in context: A214629 A330696 A103803 * A068801 A215504 A109650

Adjacent sequences:  A188674 A188675 A188676 * A188678 A188679 A188680

KEYWORD

nonn

AUTHOR

Benoit Cloitre & Robert G. Wilson v, Apr 08 2011

STATUS

approved

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Last modified August 4 14:04 EDT 2020. Contains 336201 sequences. (Running on oeis4.)