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A005754 Number of planted identity matched trees with n nodes.
(Formerly M1765)
0
1, 1, 2, 7, 24, 95, 388, 1650, 7183, 31965, 144502, 662241, 3068942, 14358678, 67729973, 321759461, 1538076291, 7392775328, 35707198905, 173221206284, 843634142771, 4123376617009, 20218897206392, 99436453714990 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

Number of rooted identity trees with n nodes and edges not attached to root are 2-colored or oriented.

REFERENCES

R. Simion, Trees with 1-factors and oriented trees, Discrete Math., 88 (1991), 93-104.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 430

N. J. A. Sloane, Transforms

Index entries for sequences related to rooted trees

FORMULA

a(n+1) is Weigh transform of A005753.

CROSSREFS

Sequence in context: A150421 A150422 A137952 * A007162 A150423 A150424

Adjacent sequences:  A005751 A005752 A005753 * A005755 A005756 A005757

KEYWORD

nonn,nice,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms, formula and comment from Christian G. Bower (bowerc(AT)usa.net), Dec 15 1999.

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.