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Least prime p such that 2n = p + g, where g is a prime primitive root of p, or 0 if there is no such prime p.
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%I #5 Mar 30 2012 17:22:47

%S 0,0,0,5,7,7,0,0,11,13,17,13,0,17,23,19,23,0,0,23,23,31,43,29,37,41,

%T 37,37,41,41,43,0,47,61,41,43,67,47,47,67,59,53,73,47,47,61,53,59,67,

%U 0,59,61,59,67,97,89,97,79,71,61,79,71,73,67,71,71,97,83,71,137,113,0,103,89

%N Least prime p such that 2n = p + g, where g is a prime primitive root of p, or 0 if there is no such prime p.

%C Goldbach meets prime primitive prime roots. Sequence A138118 gives the number of representations for each 2n and sequence A138307 lists the values of 2n that are not represented.

%H T. D. Noe, <a href="/A138306/b138306.txt">Table of n, a(n) for n=1..1000</a>

%Y Cf. A138305 (prime primitive roots).

%K nonn

%O 1,4

%A _T. D. Noe_, Mar 14 2008