

A103709


Smallest prime p such that both p +/ 2n are primes closest to p, or zero if no such prime exists.


1



5, 0, 53, 0, 0, 211, 0, 0, 20201, 0, 0, 16787, 0, 0, 69623, 0, 0, 255803, 0, 0, 247141, 0, 0, 3565979, 0, 0, 6314447, 0, 0, 4911311, 0, 0, 12012743, 0, 0, 23346809, 0, 0, 43607429, 0, 0, 34346287, 0, 0, 36598607, 0, 0, 51042053, 0, 0, 460475569, 0, 0
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OFFSET

1,1


COMMENTS

Such triples of primes occur only for n divisible by 3 (except for the first term with n=1).


LINKS

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


FORMULA

p2n, p and p+2n are three successive primes and p is the least such prime.


EXAMPLE

a(36)=23346809 because 2334680972, 23346809 and 23346809+72 are three successive primes and 23346809 is the least such prime.


CROSSREFS

Cf. A054342, A102723, A023186.
Sequence in context: A186746 A208928 A297206 * A122045 A294314 A266324
Adjacent sequences: A103706 A103707 A103708 * A103710 A103711 A103712


KEYWORD

nonn


AUTHOR

Zak Seidov, Feb 12 2005


EXTENSIONS

More terms from Robert G. Wilson v, Feb 22 2005
Definition, Formula, and Example clarified by Jonathan Sondow, Oct 27 2017


STATUS

approved



