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a(n) is the smallest n-digit zeroless prime such that the sum of the two numbers that result from splitting a(n) between any two of its digits is a distinct prime, or 0 if there is no such n-digit prime.
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%I #10 Sep 01 2014 01:45:56

%S 11,281,2267,26881,464447,6462667,0,0,0,0,0,0,0,0,0,0,0

%N a(n) is the smallest n-digit zeroless prime such that the sum of the two numbers that result from splitting a(n) between any two of its digits is a distinct prime, or 0 if there is no such n-digit prime.

%C The last digit is always odd and every other digit is even (except for a(1) = 11). - _Sean A. Irvine_, Apr 11 2010

%e a(4) = 2267. 2 + 267 = 269, which is prime. 22 + 67 = 89, which is prime. 226 + 7 = 233, which is prime.

%e a(2) is NOT 227 because 2 + 27 = 29 and 22 + 7 = 29 are the same prime. [From _Sean A. Irvine_, Apr 11 2010]

%K base,more,nonn

%O 2,1

%A _Ray G. Opao_, Mar 23 2005

%E More terms from _Sean A. Irvine_, Apr 11 2010

%E a(13)-a(18) from _Hiroaki Yamanouchi_, Aug 31 2014