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A091637
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Number of primes less than 10^n which do not contain the digit 3.
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10
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3, 16, 102, 668, 4715, 34813, 265015, 2067152, 16413535, 132200223, 1076692515, 8849480283, 73288053795, 610860050965
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OFFSET
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1,1
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COMMENTS
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Number of primes less than 10^n after removing any primes with at least one digit 3.
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LINKS
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FORMULA
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EXAMPLE
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a(2)=16 because there are 25 primes less than 10^2, 9 have at least one digit 3; 25-9 = 16.
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MATHEMATICA
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NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; c = 0; p = 1; Do[ While[ p = NextPrim[p]; p < 10^n, If[ Position[ IntegerDigits[p], 3] == {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* Robert G. Wilson v, Feb 02 2004 *)
Table[Count[Prime[Range[PrimePi[10^n]]], _?(DigitCount[#, 10, 3]==0&)], {n, 8}] (* Harvey P. Dale, Oct 04 2011 *)
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PROG
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(PARI) good(n)=n=eval(Vec(Str(n))); for(i=1, #n, if(n[i]==3, return(1))); 0
(Python)
from sympy import primerange
def a(n): return sum('3' not in str(p) for p in primerange(2, 10**n))
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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