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%I #21 Oct 05 2020 17:53:15
%S 1,3,17,37,9107,156335,679083,1068131,4883039,101691357
%N n is such that partial sum of pi(k) from 1 to n is divisible by n.
%C a(11) > 10^12. - _Donovan Johnson_, Mar 19 2011
%C a(11) > 10^13. - _Lucas A. Brown_, Oct 05 2020
%F Solutions to Mod[A046992(x), x]=0
%e a(3) = 17 because 0+1+2+2+3+3+4+4+4+4+5+5+6+6+6+6+7 = 68 = 4*17.
%t s = 0; Do[s = s + PrimePi[n]; If[ IntegerQ[s/n], Print[{n, s, s/n}]], {n, 1, 10^8}]
%Y Cf. A046992, A000720, A073163, A073164, A073224.
%K nonn,more
%O 1,2
%A _Labos Elemer_, Jul 18 2002
%E Edited and extended by _Robert G. Wilson v_, Jul 20 2002
%E a(10) from _Donovan Johnson_, Dec 15 2009
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