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%I #10 Feb 20 2019 16:00:56
%S 1,13,7,3,11,9,27,19,23,33,31,29,39,17,37,47,49,51,41,53,59,67,57,43,
%T 73,61,21,69,63,71,77,79,87,81,93,83,99,91,113,97,119,121,111,89,127,
%U 137,131,117,129,123,133,151,143,163,159,153,177,187,193,157,147,211,161,171,173,167,179,169,181,199,221,213,217,223,191,227
%N Lexicographically earliest sequence of different terms starting with a(1) = 1 such that the n-th digit of the sequence, placed in front of a(n) and then concatenated, produces a prime.
%C No digit 0 is admitted in a(n) in order to avoid leading zeroes after the concatenation.
%H Jean-Marc Falcoz, <a href="/A324279/b324279.txt">Table of n, a(n) for n = 1..10002</a>
%e The 1st digit of the sequence (1) concatenated to the 1st term = 11 (prime);
%e the 2nd digit of the sequence (1) concatenated to the 2nd term = 113 (prime);
%e the 3rd digit of the sequence (3) concatenated to the 3rd term = 37 (prime);
%e the 4th digit of the sequence (7) concatenated to the 4th term = 73 (prime);
%e the 5th digit of the sequence (3) concatenated to the 5th term = 311 (prime);
%e the 6th digit of the sequence (1) concatenated to the 6th term = 19 (prime);
%e the 7th digit of the sequence (1) concatenated to the 7th term = 127 (prime);
%e the 8th digit of the sequence (9) concatenated to the 8th term = 919 (prime);
%e the 9th digit of the sequence (2) concatenated to the 9th term = 223 (prime);
%e etc.
%Y Cf. A306321, A306311, A324280, A324281 and A324282 where the same idea is used.
%K base,nonn
%O 1,2
%A _Eric Angelini_ and _Jean-Marc Falcoz_, Feb 20 2019
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