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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A085983 Number of 9's in decimal expansion of prime(n).

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%I A085983 #10 May 08 2018 08:38:21
%S A085983 0,0,0,0,0,0,0,1,0,1,0,0,0,0,0,0,1,0,0,0,0,1,0,1,1,0,0,0,1,0,0,0,0,1,
%T A085983 1,0,0,0,0,0,1,0,1,1,1,2,0,0,0,1,0,1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,
%U A085983 0,1,0,1,0,0,1,0,1,1,0,1,1,0,0,0,1,0,1,0,0,0,0,1,0,1,2,0,1,0,0,0,0,0,0,1,0
%N A085983 Number of 9's in decimal expansion of prime(n).
%H A085983 Reinhard Zumkeller, <a href="/A085983/b085983.txt">Table of n, a(n) for n = 1..10000</a>
%t A085983 DigitCount[#,10,9]&/@Prime[Range[110]] (* _Harvey P. Dale_, May 08 2018 *)
%o A085983 (Haskell)
%o A085983 a085983 = count9 0 . a000040 where
%o A085983    count9 c x | d == 9    = if x < 10 then c + 1 else count9 (c + 1) x'
%o A085983               | otherwise = if x < 10 then c else count9 c x'
%o A085983               where (x', d) = divMod x 10
%o A085983 -- _Reinhard Zumkeller_, Apr 08 2014
%Y A085983 Cf. 0's A085974, 1's A085975, 2's A085976, 3's A085977, 4's A085978, 5's A085979, 6's A085980, 7's A085981, 8's A085982.
%K A085983 base,nonn
%O A085983 1,46
%A A085983 _Jason Earls_, Jul 06 2003