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Primes with digital product = 5.
12

%I #14 Sep 08 2022 08:45:18

%S 5,151,1151,1511,511111,1111151,115111111,1111115111,1115111111,

%T 1151111111,111111111511,111511111111,1111151111111,5111111111111,

%U 111111151111111,111151111111111,5111111111111111,111115111111111111111,1111111111111111111511

%N Primes with digital product = 5.

%H Robert Israel, <a href="/A107691/b107691.txt">Table of n, a(n) for n = 1..1000</a>

%p select(isprime,[seq(seq((10^m-1)/9 + 4*10^j,j=0..m-1),m=1..40)]); # _Robert Israel_, Jan 03 2017

%t Flatten[ Table[ Select[ Sort[ FromDigits /@ Permutations[Flatten[{5, Table[1, {n}]} ]]], PrimeQ[ # ] &], {n, 0, 21}]]

%t Select[Prime[Range[3 10^6]], Times@@IntegerDigits[#] == 5 &] (* _Vincenzo Librandi_, Jul 27 2016 *)

%o (Magma) [p: p in PrimesUpTo(3*10^8) | &*Intseq(p) eq 5]; // _Vincenzo Librandi_, Jul 27 2016

%Y Cf. A004022, A107612, A107689, A107690, A107692, A107693, A107694, A107695, A107696, A107697, A107698.

%K base,nonn

%O 1,1

%A _Zak Seidov_ and _Robert G. Wilson v_, May 20 2005