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A046705 Palindromic primes whose product of digits is a prime. 1
2, 3, 5, 7, 131, 151, 11311, 1117111, 111111151111111, 111111111111111111131111111111111111111, 1111111111111111111111111111111117111111111111111111111111111111111, 1111111111111111111111111111111111111111111115111111111111111111111111111111111111111111111 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Except for the first 4 terms, a subsequence of A088281. - Chai Wah Wu, Dec 17 2015

Subsequence of A028842, of A046703, and also of A117058. - Michel Marcus, Dec 18 2015

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..15

MATHEMATICA

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

PROG

(Python)

from __future__ import division

from sympy import isprime

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

CROSSREFS

Cf. A028842, A046703, A088281, A117058.

Sequence in context: A082805 A071119 A157869 * A054218 A075048 A281021

Adjacent sequences:  A046702 A046703 A046704 * A046706 A046707 A046708

KEYWORD

base,nonn

AUTHOR

Felice Russo

STATUS

approved

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Last modified December 5 10:11 EST 2021. Contains 349543 sequences. (Running on oeis4.)