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.
%I A119293 #27 May 02 2019 15:12:02
%S A119293 3,26,339,4070,55213,632418,7133747,82051293,1041785731,12182327373,
%T A119293 137771632675,1525041000685
%N A119293 Total number of 2's digits in the first 10^n primes.
%C A119293 Count the 2's digits in 10^n primes.
%e A119293 At a(1)=3 there are 3 2's digits in the first 10^1 primes.
%p A119293 A119293 := proc(n) option remember: local k,s,lim: if(n=0)then return 1:fi: lim:=10^n: s:=procname(n-1): for k from 10^(n-1)+1 to lim do s:=s+nops([SearchAll("2",convert(ithprime(k),string))]): od: return s: end: seq(A119293(n),n=1..4); # _Nathaniel Johnston_, May 09 2011
%t A119293 Table[Count[IntegerDigits[Prime[Range[10^n]]], 2, 2], {n, 6}] (* _Robert Price_, May 02 2019 *)
%Y A119293 Cf. A119290, A119291-A119292, A119294-A119300.
%K A119293 more,nonn,base
%O A119293 1,1
%A A119293 _Enoch Haga_, May 13 2006
%E A119293 Offset changed from 0 to 1 by _Nathaniel Johnston_, May 09 2011
%E A119293 a(8)-a(11) from _Robert Price_, Nov 05 2013
%E A119293 a(12) from _Marek Hubal_, Mar 04 2019