%I
%S 2,3,2,1,5,5,5,5,6,6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,9,10,10,10,10,10,11,
%T 11,11,11,11,12,12,12,12,12,13,13,13,13,13,13,14,14,14,14,14,14,15,15,
%U 15,15,15,15,16,16,16,16,16,16,17,17,17,17,17,17,17,18,18,18,18,18,18,18
%N Lexicographically earliest sequence of positive integers such that n occurs a(n)1 times, starting at n=1.
%e a(1)=2 because a(1)=1 would create a contradiction (1 would have appeared twice in the two sequences, not once). a(1)=2 implies that 1 appears once in this sequence; the first term that can equal 1 without creating a contradiction is a(4).
%Y A081315 is the corresponding sequence for nonnegative integers, see also A001462.
%K easy,nonn
%O 1,1
%A _Matthew Vandermast_, Mar 18 2003
%E Definition edited by _Benoit Jubin_, May 01 2010
