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A231793
Count of the first 10^n primes containing at least one 6's digit.
0
0, 10, 281, 3304, 39155, 445067, 5257963, 56668992, 607124788, 6426731531, 68792548151
OFFSET
1,2
FORMULA
a(n) ~ 10^n. - Charles R Greathouse IV, May 21 2014
EXAMPLE
a(2)=10 because there are 10 primes not greater than 541 (the 100th prime) that contain a 6's digit. Namely: 61, 67, 163, 167, 263, 269, 367, 461, 463, 467.
MATHEMATICA
cnt = 0; Table[Do[p = Prime[k]; If[MemberQ[IntegerDigits[p], 6], 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