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A101388 Number of n-vertex unlabeled digraphs without endpoints. 0
1, 1, 8, 137, 7704, 1413982 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..6.

CROSSREFS

Cf. A100548 (labeled case), A004110, A004108, A059166, A059167.

Sequence in context: A134053 A136472 A145404 * A050789 A187236 A091060

Adjacent sequences:  A101385 A101386 A101387 * A101389 A101390 A101391

KEYWORD

more,nonn

AUTHOR

Goran Kilibarda, Zoran Maksimovic, Vladeta Jovovic, Jan 14 2005

STATUS

approved

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Last modified June 20 05:42 EDT 2013. Contains 226419 sequences.