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A195351 Numbers n such that there are no primes in the range [2^n-n, 2^n+n]. 0
0, 25, 27, 45, 49, 97, 99, 113, 139, 176, 186, 208, 216, 227, 232, 259, 298, 309, 332, 358, 362, 364, 387, 490, 631, 659, 662, 676, 698, 705, 718, 726, 737, 747, 781, 849, 860, 862, 901, 913, 918, 936, 958, 965, 966, 992, 998 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If a(n) is prime then it is not in A000043. [Alonso del Arte, Oct 07 2011]

LINKS

Table of n, a(n) for n=1..47.

FORMULA

A192454(a(n))=0.

MATHEMATICA

Select[Range[0, 49], PrimePi[2^# - # - 1] == PrimePi[2^# + #] &] (* Alonso del Arte, Oct 07 2011 *)

CROSSREFS

Cf. A192454

Sequence in context: A239523 A129820 A096522 * A015734 A221617 A083806

Adjacent sequences:  A195348 A195349 A195350 * A195352 A195353 A195354

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Sep 16 2011

STATUS

approved

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Last modified December 10 15:13 EST 2016. Contains 279003 sequences.