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%I #7 Dec 05 2013 19:57:07
%S 2,13,103,1009,10007,100019,1000033,10000019,100000007,1000000007,
%T 10000000019,100000000019,1000000000039,10000000000037,
%U 100000000000031,1000000000000037,10000000000000061,100000000000000013
%N Least n-digit prime whose digit permutations yield at least n distinct primes, or 0 if no such prime exists.
%C Conjecture: No term is zero.
%C Leading zeros do not add to the digit count of a(n) but to the digit-count of the permutations. In a(5)=10007, the permutations 10007, 00107, 00017, 70001, 07001, 00701 and 00071 are all primes and their number is >=5. - _R. J. Mathar_, Feb 07 2008
%C In a variant where leading zeros may enhance the digit count of a(n), the sequence were 2, 13, 13, 13, 17, 17, 17, 17, 17, 17, 17, 17, 113, 113, 113,.... where 13 acts as a 2-digit prime, as the 3-digit prime 013 and as the 4-digit prime 0013, generating 13, 31 and 103. - _R. J. Mathar_, Feb 07 2008
%e a(4) = 1009: the four primes arising as digit permutations are 9001, 1009, 0019 and 0109.
%Y Cf. A000040, A046810, A131371.
%K base,easy,nonn
%O 1,1
%A _Amarnath Murthy_, Nov 07 2005
%E Corrected and extended by _R. J. Mathar_, Feb 07 2008
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