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%I #28 Nov 14 2016 13:07:56
%S 1,3,7,9,11,17,21,23,13,19,27,29,33,47,39,41,31,57,61,37,43,63,67,53,
%T 49,51,59,69,71,77,83,79,73,81,91,87,97,109,89,101,111,113,99,1037,
%U 121,107,93,103,123,127,129,131,119,1023,1031,117,1039,133,1009,153,157,141,143,139,137,149,159,161,151,163,171
%N The concatenation of |a(n)-a(n+1)| and a(n+1) is prime. Terms are distinct.
%C The sequence starts with a(1) = 1 and is always extended with the smallest integer not yet present that does not lead to a contradiction. This sequence is conjectured to be a permutation of the odd integers not ending with the digit “5”.
%C A variant of A275602
%H Jean-Marc Falcoz, <a href="/A275386/b275386.txt">Table of n, a(n) for n = 1..7856</a>
%e |1-3| = 2 and 23 is prime; |3-7| = 4 and 47 is prime; |7-9| = 2 and 29 is prime; |9-11| = 2 and 211 is prime; |11-17| = 6 and 617 is prime; etc.
%t a = {1}; Do[k = 1; While[Or[! PrimeQ@ FromDigits[IntegerDigits[Abs[a[[i - 1]] - k]]~Join~IntegerDigits[k]], MemberQ[a, k]], k++]; AppendTo[a, k], {i, 2, 71}]; a (* _Michael De Vlieger_, Nov 14 2016 *)
%Y cf. A275602
%K nonn,base
%O 1,2
%A _Eric Angelini_ and _Jean-Marc Falcoz_, Nov 14 2016