%N Smallest number at which a new Haar graph is encountered.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HaarGraph.html">Haar Graph</a>
%e Haar(5) and Haar(6) are both isomorphic to the 6-cycle graph, so 5 appears in the sequence but 6 does not.
%Y Cf. A272919 (numbers that uniquely index a Haar graph).
%A _Eric W. Weisstein_, Feb 07 2008
%E Name clarified by _Eric W. Weisstein_, Aug 19 2017