|
Search: id:A004251
|
|
|
| A004251 |
|
Number of graphical partitions (degree-vectors for simple graphs with n vertices, or possible ordered row-sum vectors for a symmetric 0-1 matrix with diagonal values 0).
(Formerly M1250)
|
|
+0
13
|
|
| 1, 2, 4, 11, 31, 102, 342, 1213, 4361, 16016, 59348, 222117, 836315, 3166852, 12042620, 45967479, 176005709, 675759564, 2600672458
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
REFERENCES
|
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
R. A. Brualdi, H. J. Ryser, Combinatorial Matrix Theory, Cambridge Univ. Press, 1992.
P. R. Stein, On the number of graphical partitions, pp. 671-684 of Proc. 9th S-E Conf. Combinatorics, Graph Theory, Computing, Congr. Numer. 21 (1978).
|
|
LINKS
|
T. M. Barnes and C. D. Savage, A recurrence for counting graphical partitions, Electronic J. Combinatorics, 2 (1995)
Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.
Index entries for sequences related to graphical partitions
Author?, Title?.
|
|
CROSSREFS
|
Cf. A000569, A004250, A004251, A029889.
Adjacent sequences: A004248 A004249 A004250 this_sequence A004252 A004253 A004254
Sequence in context: A148166 A148167 A148168 this_sequence A148169 A110140 A115625
|
|
KEYWORD
|
nonn,more
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com).
|
|
EXTENSIONS
|
More terms from TORSTEN.SILLKE(AT)LHSYSTEMS.COM, using Cor. 6.3.3, Th. 6.3.6, Cor. 6.2.5 of Brualdi-Ryser.
a(19) from Herman Jamke (hermanjamke(AT)fastmail.fm), May 19 2007
|
|
|
Search completed in 0.004 seconds
|
