A231788 Count of the first 10^n primes containing at least one 2's digit.

3, 23, 303, 3503, 44448, 487900, 5289359, 57794031, 658775109, 7212208422, 77028673251

Offset: 1

Author

Robert Price, Nov 13 2013

Keywords

• more
• nonn
• base

Examples

			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.
		

Crossrefs

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

Programs

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 *)

Formula

a(n) ~ 10^n. - Charles R Greathouse IV, May 21 2014