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URL: https://oeis.org/A231592

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A231592
Total number of 3's digits in primes less than 10^n.
0
1, 9, 75, 677, 6229, 58770, 564650, 5472472, 53396224, 523382007, 5148387363, 50778098799, 501864775685, 4968288427006
OFFSET
1,2
EXAMPLE
a(2)=9, since there are 9 3's in primes less than 100. Namely: 3, 13, 23, 31, 37, 43, 53, 73, 83.
MATHEMATICA
Table[Count[IntegerDigits[Prime[Range[PrimePi[10^n - 1]]]], 3, 2], {n, 7}] (* Robert Price, Jun 16 2019 *)
KEYWORD
nonn,base,more
AUTHOR
Robert Price, Nov 11 2013
EXTENSIONS
a(14) from Giovanni Resta, Jul 20 2015
STATUS
approved