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A130132
Number of trees on n vertices which are not lobsters.
5
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 4, 19, 77, 287, 1002, 3365, 10853, 34088, 104574, 315116, 935321, 2743374, 7966723, 22951010, 65681536, 186961873, 529845497, 1496245171, 4213181063, 11836671278, 33195092417, 92966480736
OFFSET
1,11
COMMENTS
Also the number of nonlinear trees on n nodes. - Andrew Howroyd, Dec 17 2020
LINKS
Tanay Wakhare, Eric Wityk, and Charles R. Johnson, The proportion of trees that are linear, Discrete Mathematics, 343.10 (2020): 112008. Also on arXiv, arXiv:1901.08502 [math.CO], 2019-2020. See Tables 1 and 2 (but beware errors).
Eric Weisstein's World of Mathematics, Lobster Graph
FORMULA
a(n) = A000055(n) - A130131(n). - Andrew Howroyd, Nov 02 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, May 11 2007
EXTENSIONS
a(15)-a(32) from Washington Bomfim, Feb 23 2011
STATUS
approved