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%I #28 Jan 15 2021 21:32:50
%S 1,14,106,1014,9902,100106,1000040,9999521,100000273,1000036012,
%T 9999956635,99999854780
%N Number of times the digit 9 appears in the first 10^n digits of Pi after the decimal point.
%D Alfred S. Posamentier and Ingmar Lehmann, A Biography of the World's Most Mysterious Number, Prometheus Books, Amherst, NY 2004, page 129.
%H Kanada Laboratory, <a href="http://www.super-computing.org/pi-decimal_current.html">Statistical Distribution Information</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PiDigits.html">Pi Digits</a>.
%e Pi = 3.1415926535..., so A099294(1) = 1, A099296(1) = 3, and a(1) = 1.
%t $MaxPrecision = 1100000; dp = Drop[ RealDigits[Pi, 10, 1000010] [[1]], 1]; Table[ Count[ Take[dp, 10^n], 9], {n, 6}]
%o (Python) # call with d = 0..8 for A099291..A099299
%o from sympy import S
%o def a(n, d=9): return str(S.Pi.n(10**n + 2))[2:-1].count(str(d))
%o print([a(n) for n in range(1, 7)]) # _Michael S. Branicky_, Jan 14 2021
%Y Cf. A000796, A099291, A099292, A099293, A099294.
%Y Cf. A099295, A099296, A099297, A099298, A099299.
%K nonn,base,more
%O 1,2
%A _Robert G. Wilson v_, Oct 11 2004
%E Name clarified by _Michael S. Branicky_, Jan 15 2021
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