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Total number of 3's digits in primes less than 10^n.
0

%I #14 Jun 16 2019 13:20:37

%S 1,9,75,677,6229,58770,564650,5472472,53396224,523382007,5148387363,

%T 50778098799,501864775685,4968288427006

%N Total number of 3's digits in primes less than 10^n.

%e a(2)=9, since there are 9 3's in primes less than 100. Namely: 3, 13, 23, 31, 37, 43, 53, 73, 83.

%t Table[Count[IntegerDigits[Prime[Range[PrimePi[10^n - 1]]]], 3, 2], {n, 7}] (* _Robert Price_, Jun 16 2019 *)

%Y Cf. A231411, A231590-A231598, A119290, A119291-A119300.

%K nonn,base,more

%O 1,2

%A _Robert Price_, Nov 11 2013

%E a(14) from _Giovanni Resta_, Jul 20 2015