%I #22 Jun 12 2015 04:06:18
%S 2,3,5,7,11,13,17,37,79,101,107,113,131,149,151,157,167,179,181,191,
%T 199,313,337,347,353,359,373,383,389,709,727,739,757,769,787,797,919,
%U 929,1009,1021,1031,1033,1061,1069,1091,1097,1103,1109,1151,1153,1181
%N Lesser of a prime/emirp pair.
%C From the set of numbers that are both prime and emirp choose the smaller one of each pair (whenever more than one decimal digit is involved).
%C A002385 is subset of this sequence.
%H Chai Wah Wu, <a href="/A141263/b141263.txt">Table of n, a(n) for n = 1..1000</a>
%e 31 does not appear since we have already seen 13.
%t pp[n_] := Module[{nr=FromDigits[Reverse[IntegerDigits[n]]]}, If[PrimeQ[nr],Sort[{n,nr}]]]; Transpose[Rest[Union[pp/@Prime[Range[200]]]]][[1]] (* _Harvey P. Dale_, Dec 18 2010 *)
%o (Python)
%o from gmpy2 import next_prime, is_prime
%o A141263_list, p = [], 1
%o for _ in range(1,10**4):
%o ....p = next_prime(p)
%o ....ps = int(str(p)[::-1])
%o ....if p <= ps and is_prime(ps):
%o ........A141263_list.append(int(p)) # _Chai Wah Wu_, Jun 11 2015
%Y Cf. A002385, A007500.
%K nonn,base
%O 1,1
%A _Artur Jasinski_, Jun 20 2008
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