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A228414
Count of the first 10^n primes which do not contain the digit 2.
0
0, 7, 77, 697, 6497, 55552, 512100, 4710641, 42205969, 341224891, 2787791578, 22971326749, 190650687957
OFFSET
0,2
FORMULA
a(n) < 9^n. - Charles R Greathouse IV, May 21 2014
EXAMPLE
a(1) = 7 since there are 7 primes less than 29 (the 10th prime) that do not contain a 2. Namely: 3, 5, 7, 11, 13, 17, 19.
MATHEMATICA
Table[Length[Select[Range[10^n], DigitCount[Prime[#], 10, 2] == 0 &]], {n, 0, 5}] (* Robert Price, Mar 23 2020 *)
KEYWORD
more,nonn,base,hard
AUTHOR
Robert Price, Nov 09 2013
EXTENSIONS
a(12) from Lucas A. Brown, Mar 19 2024
STATUS
approved