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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A007109 Number of labeled 2-regular oriented graphs with n nodes.
(Formerly M5164)
1
1, 0, 0, 0, 0, 24, 570, 27900, 1827630, 152031600, 15453884376, 1884221030160, 271711899360000, 45788222207669040, 8922353083744943700, 1991728039234615305624, 505133808398958249480060 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,6

REFERENCES

R. W. Robinson, personal communication.

R. W. Robinson, Numerical implementation of graph counting algorithms, AGRC Grant, Math. Dept., Univ. Newcastle, Australia, 1982.

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

LINKS

R. W. Robinson, Table of n, a(n) for n = 0..48

CROSSREFS

Sequence in context: A218726 A203487 A007110 * A158538 A171329 A077423

Adjacent sequences:  A007106 A007107 A007108 * A007110 A007111 A007112

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

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 July 23 12:35 EDT 2019. Contains 325254 sequences. (Running on oeis4.)