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%I #17 Jul 31 2017 10:01:10
%S 1,1,1,1,1,1,18,3,1,1
%N Number of nonisomorphic (3,n) cage graphs.
%H Andries E. Brouwer, <a href="http://www.win.tue.nl/~aeb/graphs/cages/cages.html">Cages</a>
%H Geoff Exoo, <a href="http://ginger.indstate.edu/ge/CAGES">Regular graphs of given degree and girth</a>
%H G. Exoo and R. Jajcay, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/DS16">Dynamic cage survey</a>, Electr. J. Combin. (2008, 2011).
%H Gordon Royle, <a href="http://staffhome.ecm.uwa.edu.au/~00013890/remote/cages/allcages.html">Cages of higher valency</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CageGraph.html">Cage Graph</a> (claims too much)
%e a(12) = 1 from the unique generalized hexagon of order 2.
%Y Cf. A000066 (size of these graphs).
%K nonn,more,hard
%O 3,7
%A _Eric W. Weisstein_
%E a(11) from B. D. McKay and W. Myrvold.