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A129524 Number of unlabeled digraphs on n vertices such that every vertex has outdegree 2. 3
0, 1, 6, 79, 1499, 35317, 967255, 29949217 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,3

LINKS

Table of n, a(n) for n=2..9.

L. Travis, [math/9811127] Graphical Enumeration: A Species-Theoretic Approach

CROSSREFS

Cf. A001373, A185193, A185194, A185303.

Sequence in context: A156929 A123796 A184553 * A131237 A024082 A132547

Adjacent sequences:  A129521 A129522 A129523 * A129525 A129526 A129527

KEYWORD

nonn

AUTHOR

Vladeta Jovovic, May 29 2007

STATUS

approved

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Last modified May 20 03:10 EDT 2019. Contains 323412 sequences. (Running on oeis4.)