A119300 Total number of 9's digits in the first 10^n primes.
2, 33, 431, 6318, 72062, 806674, 9004550, 104220797, 1131743629, 12266783460, 131900123107, 1447662128808
Offset: 1
Examples
At a(3)=431 there are 431 9's digits in the first 10^3 = 1000 primes.
Programs
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Maple
A119300 := proc(n) option remember: local k,s,lim: if(n=0)then return 0:fi: lim:=10^n: s:=procname(n-1): for k from 10^(n-1)+1 to lim do s:=s+nops([SearchAll("9",convert(ithprime(k),string))]): od: return s: end: seq(A119300(n),n=1..4); # Nathaniel Johnston, May 09 2011
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Mathematica
cnt=0; k=0; Table[While[k++; cnt=cnt+DigitCount[Prime[k], 10, 9];k < 10^n]; cnt, {n, 5}] (* T. D. Noe, May 10 2011 *)
Extensions
a(8)-a(11) from Robert Price, Nov 05 2013
a(12) from Marek Hubal, Mar 04 2019