%I #9 Feb 04 2023 20:58:13
%S 0,0,1,0,1,2,0,2,5,6,0,2,9,13,14,0,3,18,32,36,37,0,3,28,67,82,87,88
%N Triangle read by rows: T(n,k) = number of edges in graph whose vertices are forests with n unlabeled nodes and degree <= k and in which two vertices are joined by an edge if the forests differ (up to isomorphism) by exactly one edge.
%C The number of nodes in this graph is given by A144215.
%H Rebecca Neville, <a href="https://web.archive.org/web/20191029092609/http://gtn.kazlow.info:80/GTN54.pdf">Graphs whose vertices are forests with bounded degree</a>, Graph Theory Notes of New York, LIV (2008), 12-21. [Wayback Machine link]
%e Triangle begins:
%e 0
%e 0 1
%e 0 1 2
%e 0 2 5 6
%e 0 2 9 13 14
%e 0 3 18 32 36 37
%e 0 3 28 67 82 87 88
%Y Cf. A144530.
%K nonn,tabl,more
%O 1,6
%A _N. J. A. Sloane_, Dec 20 2008
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