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A119296
Total number of 5's digits in the first 10^n primes.
5
1, 15, 327, 3904, 47525, 590450, 7087898, 79504457, 887852429, 9862623240, 110885914721, 1199346258292
OFFSET
1,2
EXAMPLE
At a(2)=15 there are 15 5's digits in the first 10^2 primes.
MAPLE
A119296 := 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("5", convert(ithprime(k), string))]): od: return s: end: seq(A119296(n), n=1..4); # Nathaniel Johnston, May 09 2011
MATHEMATICA
Table[Total[DigitCount[#, 10, 5]&/@Prime[Range[10^n]]], {n, 7}] (* Vincenzo Librandi, Sep 09 2015 *)
KEYWORD
more,nonn,base
AUTHOR
Enoch Haga, May 13 2006
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
STATUS
approved