login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A139621 Table read by rows: T(n,k) is the number of connected directed multigraphs with loops and no vertex of degree 0, with n arcs and k vertices. 4
1, 1, 1, 4, 3, 1, 8, 15, 8, 1, 16 (list; graph; refs; listen; history; internal format)
OFFSET

1,4

COMMENTS

Length of the n^th row: n+1.

T(n,1) = 1, T(n,2) = T139654(n,2) - floor(n/2), T(n,n+1) = A022017(n).

Row sums: A139626.

LINKS

B. Jubin, Sequences contributed to the OEIS.

CROSSREFS

Cf. A136564, A139622.

Sequence in context: A128007 A098458 A165914 * A196841 A165732 A197698

Adjacent sequences:  A139618 A139619 A139620 * A139622 A139623 A139624

KEYWORD

nonn

AUTHOR

Benoit Jubin (benoit_jubin(AT)yahoo.fr), May 01 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 13 08:12 EST 2012. Contains 205451 sequences.