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A141263
Lesser of a prime/emirp pair.
2
2, 3, 5, 7, 11, 13, 17, 37, 79, 101, 107, 113, 131, 149, 151, 157, 167, 179, 181, 191, 199, 313, 337, 347, 353, 359, 373, 383, 389, 709, 727, 739, 757, 769, 787, 797, 919, 929, 1009, 1021, 1031, 1033, 1061, 1069, 1091, 1097, 1103, 1109, 1151, 1153, 1181
OFFSET
1,1
COMMENTS
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).
A002385 is subset of this sequence.
EXAMPLE
31 does not appear since we have already seen 13.
MATHEMATICA
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 *)
PROG
(Python)
from gmpy2 import next_prime, is_prime
A141263_list, p = [], 1
for _ in range(1, 10**4):
p = next_prime(p)
ps = int(str(p)[::-1])
if p <= ps and is_prime(ps):
A141263_list.append(int(p)) # Chai Wah Wu, Jun 11 2015
CROSSREFS
Sequence in context: A118725 A117835 A120639 * A016114 A263499 A258706
KEYWORD
nonn,base
AUTHOR
Artur Jasinski, Jun 20 2008
STATUS
approved