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A046705 Palindromic primes whose product of digits is a prime. 1

%I

%S 2,3,5,7,131,151,11311,1117111,111111151111111,

%T 111111111111111111131111111111111111111,

%U 1111111111111111111111111111111117111111111111111111111111111111111,1111111111111111111111111111111111111111111115111111111111111111111111111111111111111111111

%N Palindromic primes whose product of digits is a prime.

%C Except for the first 4 terms, a subsequence of A088281. - _Chai Wah Wu_, Dec 17 2015

%C Subsequence of A028842, of A046703, and also of A117058. - _Michel Marcus_, Dec 18 2015

%H Chai Wah Wu, <a href="/A046705/b046705.txt">Table of n, a(n) for n = 1..15</a>

%t t = Prime[Range[4]]; Union[Select[Flatten[Table[NestList[FromDigits[Flatten[{1, IntegerDigits[#], 1}]] &, n, 45], {n, t}]], PrimeQ]] (* _Jayanta Basu_, Jun 27 2013 *)

%o (Python)

%o from __future__ import division

%o from sympy import isprime

%o A046705_list = [n for n in ((10**(2*l+1)-1)//9+d*10**l for l in range(100) for d in [1,2,4,6]) if isprime(n)] # _Chai Wah Wu_, Dec 17 2015

%Y Cf. A028842, A046703, A088281, A117058.

%K base,nonn

%O 1,1

%A _Felice Russo_

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Last modified November 11 18:50 EST 2019. Contains 329031 sequences. (Running on oeis4.)