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A277796 Number of trees with n unlabeled nodes such that all nodes of degree >2 lie on a single path. 0
1, 1, 1, 1, 2, 3, 6, 11, 23, 47, 105, 231, 537 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

First differs from A000055 at a(10).

First differs from A130131 at a(12), n >= 1.

LINKS

Table of n, a(n) for n=0..12.

EXAMPLE

a(10) = 105 counts all trees except for the following.

     o   o

      \ /

       o

       |

       o

     /   \

    o     o

   / \   / \

  o   o o   o

CROSSREFS

Cf. A000055, A130131, A277795.

Sequence in context: A211694 A303586 A130131 * A123465 A000055 A217312

Adjacent sequences:  A277793 A277794 A277795 * A277797 A277798 A277799

KEYWORD

nonn,more

AUTHOR

Gabriel Burns, Oct 31 2016

STATUS

approved

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Last modified October 16 13:12 EDT 2018. Contains 316263 sequences. (Running on oeis4.)