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Total number of 4's digits in the first 10^n primes.
6

%I #19 Jun 10 2019 00:48:38

%S 0,27,311,3919,47647,628061,7098709,79587350,888504625,10169426048,

%T 110936566287,1199775766812

%N Total number of 4's digits in the first 10^n primes.

%e At a(2)=27 there are 27 4's digits in the first 10^2 primes.

%p A119295 := 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("4",convert(ithprime(k),string))]): od: return s: end: seq(A119295(n),n=1..4); # _Nathaniel Johnston_, May 09 2011

%t Accumulate@Table[c = 0; For[i = 10^(n - 1) + 1, i <= 10^n, i++, c += Count[IntegerDigits[Prime[i]], 4]]; c, {n, 6}] (* _Robert Price_, Jun 09 2019 *)

%Y Cf. A119290, A119291-A119294, A119296-A119300.

%K more,nonn,base

%O 1,2

%A _Enoch Haga_, May 13 2006

%E Offset changed from 0 to 1 by _Nathaniel Johnston_, May 09 2011

%E a(8)-a(11) from _Robert Price_, Nov 05 2013

%E a(12) from _Marek Hubal_, Mar 04 2019