%I
%S 1,3,5,7,21,92,209,415,947,1403,8484,26675,70708,205919,
%T 737729,2162013,4741957,13992966,77928220,122866869,374649610,
%U 1334960954,5317831008,9896721062,38014073661
%N Difference between the number of primes with n digits (A006879) and the difference of consecutive integers nearest to Li(10^n)  Li(2) (see A228067).
%C The sequence A006879(n) is always < A228067(n) for 1<=n<=25.
%C The sequence (A228067) yields an average relative difference in absolute value, i.e. <ARD(A228068)> = Average(Abs(A228068(n))/ (A006879(n)) = 1.75492…x10^2 for 1<=n<=25.
%C Note that A190802(n)=(Li(10^n)Li(2)) is not defined for n=0. Its value is set arbitrarily to 0.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PrimeCountingFunction.html">Prime Counting Function</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LogarithmicIntegral.html">Logarithmic Integral</a>
%F a(n) = A006879(n)  A228067(n).
%Y Cf. A006880, A006879, A228067, A228066.
%K sign
%O 1,2
%A _Vladimir Pletser_, Aug 06 2013
