A277796 - OEIS

A277796

Number of trees with n unlabeled nodes such that all nodes of degree >2 lie on a single path.

1, 1, 1, 1, 2, 3, 6, 11, 23, 47, 105, 231, 537

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OFFSET

0,5

COMMENTS

First differs from A000055 at a(10).

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

LINKS

EXAMPLE

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

o o

\ /

/ \

o o

/ \ / \

o o o o

CROSSREFS

KEYWORD

nonn,more

AUTHOR

STATUS

approved