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%I #13 Dec 11 2016 06:55:33
%S 1,1,1,1,2,3,6,11,23,47,105,231,537
%N Number of trees with n unlabeled nodes such that all nodes of degree >2 lie on a single path.
%C First differs from A000055 at a(10).
%C First differs from A130131 at a(12), n >= 1.
%e a(10) = 105 counts all trees except for the following.
%e o o
%e \ /
%e o
%e |
%e o
%e / \
%e o o
%e / \ / \
%e o o o o
%Y Cf. A000055, A130131, A277795.
%K nonn,more
%O 0,5
%A _Gabriel Burns_, Oct 31 2016