%I #14 Aug 17 2015 16:32:47

%S 1,2,3,4,5,6,7,8,9,12,34,56,78,91,234,567,891,2345,6789,12345,67891,

%T 234567,891234,5678912,34567891,234567891,2345678912,3456789123,

%U 4567891234,5678912345,6789123456,7891234567,8912345678,9123456789

%N a(1) = 1; for n > 1, a(n) > a(n-1) is the smallest number such that the concatenation a(1)a(2)a(3)... forms a cyclic concatenation of 123456789 (of nonzero digits).

%H Ivan Neretin, <a href="/A081549/b081549.txt">Table of n, a(n) for n = 1..500</a>

%t a = {1}; c = 0; Do[c = 10 c + Mod[n, 9] + 1; If[c > a[[-1]], AppendTo[a, c]; c = 0], {n, 170}]; a (* _Ivan Neretin_, Aug 14 2015 *)

%Y Cf. A165307 (non-monotonic version), A007923 (version with strictly increasing length).

%K base,easy,nonn

%O 1,2

%A _Amarnath Murthy_, Apr 01 2003

%E Corrected and extended by _Sean A. Irvine_, Apr 18 2010