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Number of primes less than 10^n having at least one digit 2.
10

%I #13 Jul 21 2015 06:05:04

%S 1,3,29,352,3357,32393,312424,3014171,29016211,279171099,2685272908,

%T 25829666453,248507003625,2391688694305

%N Number of primes less than 10^n having at least one digit 2.

%e a(2) = 3 because of the 25 primes less than 10^2, 3 have at least one digit 2.

%Y a(n) + A091636(n) = A006880(n).

%Y Cf. A091644, A091645, A091647, A091705, A091706, A091707, A091708, A091709, A091710.

%K nonn,base

%O 1,2

%A _Enoch Haga_, Jan 30 2004

%E Edited and extended by _Robert G. Wilson v_, Feb 02 2004

%E 3 more terms from _Ryan Propper_, Aug 20 2005

%E a(13) from _Robert Price_, Nov 11 2013

%E a(14) from _Giovanni Resta_, Jul 21 2015