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Numbers that are both lucky and emirp.
1

%I #7 Nov 19 2019 03:36:37

%S 13,31,37,73,79,739,769,937,991,1009,1021,1201,1231,1249,1471,1597,

%T 1723,1831,1879,1933,3049,3109,3121,3163,3301,3433,3571,3613,3697,

%U 3889,7207,7321,7459,7507,7603,7687,7717,7951,7963,9349,9403,9421,9547,9613,9643

%N Numbers that are both lucky and emirp.

%H Amiram Eldar, <a href="/A129864/b129864.txt">Table of n, a(n) for n = 1..10000</a>

%F A000959 INTERSECTION A006567. a(n) is n element of A000959 AND a(n) is an element of A000040 AND R(a(n)) = A004086(a(n)) is an element of A000040.

%e a(9) = 1009 because 1009 is a lucky number A000959(154) and 1009 is an emirp because 1009 is prime and R(1009) = 9001 is prime (but is not lucky).

%Y Cf. A000040, A000959, A004086, A006567, A031157.

%K base,easy,nonn,less

%O 1,1

%A _Jonathan Vos Post_, May 23 2007

%E Corrected and extended by _R. J. Mathar_, Jun 12 2007