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Total number of 1's digits in the first 10^n primes.
7

%I #23 May 03 2019 08:42:07

%S 5,55,574,7043,102370,1222003,13896979,152844768,1611113572,

%T 16626301609,171878734261,1781706224877

%N Total number of 1's digits in the first 10^n primes.

%e At a(1)=5 there are 5 1's digits in the first 10^1 primes.

%p A119292 := 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("1",convert(ithprime(k),string))]): od: return s: end: seq(A119292(n),n=1..4); # _Nathaniel Johnston_, May 09 2011

%t Table[Count[IntegerDigits[Prime[Range[10^n]]], 1, 2], {n, 6}] (* _Robert Price_, May 02 2019 *)

%o (PARI) my(x=10, i=0, j=0); forprime(p=1, , j++; my(d=digits(p)); i+=#setintersect(vecsort(d), vector(#d, t, 1)); if(j==x, print1(i, ", "); x=10*x)) \\ _Felix Fröhlich_, May 02 2019

%Y Cf. A119290, A119291, A119293-A119300.

%K more,nonn,base

%O 1,1

%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