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A046705
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Palindromic primes whose product of digits is a prime.
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1
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2, 3, 5, 7, 131, 151, 11311, 1117111, 111111151111111, 111111111111111111131111111111111111111, 1111111111111111111111111111111117111111111111111111111111111111111, 1111111111111111111111111111111111111111111115111111111111111111111111111111111111111111111
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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t = Prime[Range[4]]; Union[Select[Flatten[Table[NestList[FromDigits[Flatten[{1, IntegerDigits[#], 1}]] &, n, 45], {n, t}]], PrimeQ]] (* Jayanta Basu, Jun 27 2013 *)
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PROG
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(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
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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