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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

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.

Sequence in context: A118974 A119020 A073191 this_sequence A110140 A115625 A056323

Adjacent sequences: A004248 A004249 A004250 this_sequence A004252 A004253 A004254

KEYWORD

nonn,more

AUTHOR

njas

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

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Last modified July 25 07:41 EDT 2008. Contains 142293 sequences.


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