%I #18 Jan 25 2013 14:45:18
%S 2,5,31,167,151,491,983,887,311,1151,1559,2111,1031,2711,4391,4271,
%T 3671,3191,5351,9551,11471,14759,8951,13751,11831,5591,19991,10391,
%U 15791,28031,30071,37511,43151,27191,40031,31391,52631,53231,35591,52391,50951
%N Least prime k such that x' = k has n solutions, where x' is the arithmetic derivative (A003415) of x.
%C It is much easier finding composite numbers having many solutions. See A189558. For odd numbers, see A189560.
%D See A003415.
%H Donovan Johnson, <a href="/A189559/b189559.txt">Table of n, a(n) for n = 0..200</a>
%F a(n) is the least prime k such that A099302(k) = n.
%Y Cf. A003415, A099302, A189558, A189560.
%K nonn
%O 0,1
%A _T. D. Noe_, Apr 24 2011