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%I #17 Jul 07 2014 11:32:10
%S 27,1465,92041,6554833,504813055,40947676475,3442465670223,
%T 296935715374179,26108021958592999,2329702677873323273,
%U 210338403560373373799,19172323465486902000641,1761408925012566646647345,162904914369466264400189781
%N Partial sum of Pi(k) from 1 to 10^n.
%H Hiroaki Yamanouchi, <a href="/A073224/b073224.txt">Table of n, a(n) for n = 1..20</a>
%F a(n) = (10^n + 1) * A006880(n) - A046731(n). - _Hiroaki Yamanouchi_, Jul 06 2014
%t s = 0; k = 1; Do[ While <= 10^n, s = s + PrimePi[k]; k++ ]; Print[s], {n, 1, 8}]
%Y Cf. A000720.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Jul 20 2002
%E a(9)-a(10) from _Donovan Johnson_, Dec 15 2009
%E a(11)-a(12) from _Donovan Johnson_, Mar 19 2011
%E a(13)-a(14) from _Hiroaki Yamanouchi_, Jul 06 2014