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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A056988 Number of weakly connected digraphs on n nodes that are not strongly connected. 0
0, 1, 8, 116, 4316, 483835, 175048780, 212125583518, 887136857205696, 13086449050056880074, 691487226135525983266460 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..11.

Eric Weisstein's World of Mathematics, Connected Digraph.

FORMULA

A003085(n)-A035512(n)

CROSSREFS

Cf. A003085, A035512.

Sequence in context: A235338 A231553 A291077 * A085699 A046914 A194494

Adjacent sequences:  A056985 A056986 A056987 * A056989 A056990 A056991

KEYWORD

nonn,more

AUTHOR

Eric W. Weisstein

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 14 17:32 EST 2019. Contains 329979 sequences. (Running on oeis4.)