A184164 List of numbers that are not the number of subtrees of some tree.

2, 4, 5, 7, 8, 9, 12, 13, 14, 16, 18, 19, 22, 23, 26, 27, 29, 31, 33, 35, 38, 39, 42, 43, 46, 50, 52, 54, 60, 65, 68, 72, 77, 89

Offset

1,1

Comments

This is a finite list of 34 numbers.

Links

Table of n, a(n) for n=1..34.

É. Czabarka, L. Székely, and S. Wagner, The inverse problem for certain tree parameters, Discrete Appl. Math., 157, 2009, 3314-3319, section 2.6.

Example

4 and 5 are in the sequence since the 2-vertex tree has 3 subtrees and an m-vertex tree (m>=3) has at least 6 subtrees.

Crossrefs

Cf. A344406 (caterpillars).

Sequence in context: A183544 A219640 A344406 * A190852 A005839 A254792

Adjacent sequences: A184161 A184162 A184163 * A184165 A184166 A184167

Keyword

nonn,fini,full

Author

Emeric Deutsch, Oct 19 2011

Status

approved