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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..11.

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 *)

CROSSREFS

Cf. A231726-A231790, A231792-A231796, A091634-A091643, A231412, A228413-A228421.

Sequence in context: A060090 A052842 A307418 * A088692 A188313 A227821

Adjacent sequences:  A231785 A231786 A231787 * A231789 A231790 A231791

KEYWORD

more,nonn,base

AUTHOR

Robert Price, Nov 13 2013

STATUS

approved

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Last modified February 27 06:59 EST 2020. Contains 332299 sequences. (Running on oeis4.)