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A091644
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Number of primes less than 10^n which have at least one digit 0.
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9
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0, 0, 15, 219, 2470, 26185, 266713, 2658107, 26198216, 256516296, 2501246232, 24320647270, 236032108530, 2287868820615
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OFFSET
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1,3
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COMMENTS
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3 additional terms, generated using a sieve program. - Ryan Propper, Aug 20 2005
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LINKS
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FORMULA
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EXAMPLE
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a(3) = 15 because of the 168 primes less than 10^3, 15 have at least one 0 digit.
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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], 0] != {}, c++ ]]; Print[c]; p--, {n, 1, 8}] (* Robert G. Wilson v, Feb 02 2004 *)
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PROG
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(Python)
from sympy import sieve # use primerange for larger terms
def digs0(n): return '0' in str(n)
def aupton(terms):
ps, alst = 0, []
for n in range(1, terms+1):
ps += sum(digs0(p) for p in sieve.primerange(10**(n-1), 10**n))
alst.append(ps)
return alst
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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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