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A231593
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Total number of 4's digits in primes less than 10^n.
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0
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0, 3, 34, 360, 3772, 39006, 397474, 4022501, 40604951, 408986159, 4113511677, 41331763006, 414971464358, 4163826451096
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OFFSET
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1,2
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LINKS
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EXAMPLE
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a(2)=3, since there are 3 4's in primes less than 100. Namely: 41, 43, 47.
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MATHEMATICA
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Table[Count[IntegerDigits[Prime[Range[PrimePi[10^n - 1]]]], 4, 2], {n, 7}] (* Robert Price, Jun 16 2019 *)
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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