%I #13 Sep 08 2022 08:44:45

%S 2,29,229,929,2999,9929,22229,99929,2222929,2229299,2292299,2299229,

%T 2922229,2992229,2992999,2999299,2999999,9222229,9922229,9929929,

%U 9929999,9999299,9999929,22229299,22292929,22299229,22929299,29229229,29229929

%N Primes that contain digits 2 and 9 only.

%H Vincenzo Librandi, <a href="/A020460/b020460.txt">Table of n, a(n) for n = 1..1000</a>

%t Flatten[Table[Select[FromDigits/@Tuples[{2,9},n],PrimeQ],{n,8}]] (* _Vincenzo Librandi_, Jul 27 2012 *)

%o (Magma) [p: p in PrimesUpTo(29229929) | Set(Intseq(p)) subset [2, 9]]; // _Vincenzo Librandi_, Jul 27 2012

%K nonn,base

%O 1,1

%A _David W. Wilson_