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%I #5 Jul 28 2015 00:04:49
%S 1,2,9,11,16
%N Numbers n such that the sum of the first n digits of Pi are divisible by n.
%C For large n, A046974(n-1)/n is very close to 4.5, so is never an integer. - _David Wasserman_, Feb 27 2008
%e a[1] = 1 since 3 is divisible by 1.
%e a[2] = 2 since 3 + 1 = 4 is divisible by 2.
%e a[3] != 3 since 3 + 1 + 4 = 8 is not divisible by 3.
%t $MaxPrecision = 2500000; pd = RealDigits[N[Pi, 2000000]][[1]]; s = 0; Do[s = s + pd[[n]]; If[ Mod[s, n] == 0, Print[n]], {n, 2000000}] (* _Robert G. Wilson v_, Oct 21 2004 *)
%Y Cf. A046974.
%K base,easy,fini,full,nonn
%O 1,2
%A Anne M. Donovan (anned3005(AT)aol.com), Oct 20 2004
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