A091644 Number of primes less than 10^n which have at least one digit 0.
0, 0, 15, 219, 2470, 26185, 266713, 2658107, 26198216, 256516296, 2501246232, 24320647270, 236032108530, 2287868820615
Offset: 1
Examples
a(3) = 15 because of the 168 primes less than 10^3, 15 have at least one 0 digit.
Programs
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Mathematica
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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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 print(aupton(7)) # Michael S. Branicky, Apr 25 2021
Extensions
Edited and extended by Robert G. Wilson v, Feb 02 2004
More terms from Ryan Propper, Aug 20 2005
a(13) from Robert Price, Nov 11 2013
a(14) from Giovanni Resta, Jul 21 2015
Comments