|
Search: id:A005641
|
|
|
| A005641 |
|
Number of 2-diregular digraphs with n nodes.
(Formerly M2757)
|
|
+0
1
|
|
| 1, 3, 8, 27, 131, 711, 5055, 41607, 389759, 4065605, 46612528, 581713045, 7846380548, 113718755478, 1762208816647, 29073392136390, 508777045979418
(list; graph; listen)
|
|
|
OFFSET
|
2,2
|
|
|
REFERENCES
|
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
M. V. S. Ramanath; T. R. Walsh, Enumeration and generation of a class of regular digraphs, J. Graph Theory 11 (1987), no. 4, 471-479.
|
|
CROSSREFS
|
Sequence in context: A104854 A030495 A074271 this_sequence A148845 A148846 A163062
Adjacent sequences: A005638 A005639 A005640 this_sequence A005642 A005643 A005644
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com).
|
|
|
Search completed in 0.002 seconds
|
