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A231788
Count of the first 10^n primes containing at least one 2's digit.
0
3, 23, 303, 3503, 44448, 487900, 5289359, 57794031, 658775109, 7212208422, 77028673251
OFFSET
1,1
FORMULA
a(n) ~ 10^n. - Charles R Greathouse IV, May 21 2014
EXAMPLE
a(1)=3 because there are 3 primes not greater than 29 (the 10th prime) that contain a 2's digit. Namely: 2, 23, 29.
MATHEMATICA
cnt = 0; Table[Do[p = Prime[k]; If[MemberQ[IntegerDigits[p], 2], cnt++], {k, 10^(n - 1) + 1, 10^n}]; cnt, {n, 5}] (* T. D. Noe, Nov 13 2013 *)
KEYWORD
more,nonn,base
AUTHOR
Robert Price, Nov 13 2013
STATUS
approved