A119294 Total number of 3's digits in the first 10^n primes.
3, 54, 569, 6500, 72717, 880415, 9616078, 105052677, 1139295891, 12676601300, 135996846047, 1450287630358
Offset: 1
Examples
At a(1)=3 there are 3 3's digits in the first 10^1 primes.
Programs
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Maple
A119294 := 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("3",convert(ithprime(k),string))]): od: return s: end: seq(A119294(n),n=1..4); # Nathaniel Johnston, May 09 2011
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Mathematica
Accumulate@Table[Count[IntegerDigits[Prime[Range[10^(n - 1) + 1, 10^n]]], 3, 2], {n, 6}] (* Robert Price, Jun 16 2019 *)
Extensions
Offset changed from 0 to 1 by Nathaniel Johnston, May 09 2011
a(8)-a(11) from Robert Price, Nov 05 2013
a(12) from Marek Hubal, Mar 04 2019