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%I #4 Mar 30 2012 17:22:47
%S 0,0,0,1,1,1,0,0,1,2,2,2,0,2,1,2,2,0,0,2,3,1,1,4,1,2,2,2,3,2,1,0,1,1,
%T 3,3,1,1,5,1,3,3,2,2,2,2,1,3,1,0,6,4,1,5,1,3,3,2,3,5,2,2,4,1,6,5,2,2,
%U 4,1,3,0,2,2,6,1,3,7,2,5,6,1,3,5,3,4,4,2,2,7,1,4,1,1,6,5,1,0,2,3,4,5,0,4,7
%N Number of ways in which 2n can be represented as p+g, where p is a prime and g is a prime primitive root of p.
%H T. D. Noe, <a href="/A138319/b138319.txt">Table of n, a(n) for n=1..10000</a>
%Y Cf. A138305 (prime primitive roots), A138306 (least p such that 2n=p+g).
%K nonn
%O 1,10
%A _T. D. Noe_, Mar 14 2008