|
Search: id:A147878
|
|
|
| A147878 |
|
The number of degree sequences with degree sum 2n representable by a connected graph (with multiple edges allowed) |
|
+0
1
|
|
| 1, 2, 5, 11, 23, 46, 86, 156, 273, 463, 766, 1241, 1969, 3073, 4723, 7157, 10711, 15850, 23206, 33654, 48373, 68955, 97544, 137002, 191125, 264955, 365127, 500349, 682018, 924982, 1248502, 1677530, 2244229, 2989952, 3967732, 5245354, 6909211
(list; graph; listen)
|
|
|
OFFSET
|
2,2
|
|
|
REFERENCES
|
Rodseth, O. J., Sellers, J. A. and Tverberg, H., Enumeration of the Degree Sequences of Non-Separable Graphs and Connected Graphs, to appear in European Journal of Combinatorics
|
|
FORMULA
|
a(n) = p(2n) - p(n-1) - 2*sum(p(j), j=0..n-2)
|
|
MAPLE
|
with(combinat): for m to 60 do printf(`%d, `, numbpart(2*m) - numbpart(m - 1) - 2*sum(numbpart(j), j = 0 .. m-2)) od:
|
|
CROSSREFS
|
Sequence in context: A124920 A064934 A005986 this_sequence A140992 A093053 A075712
Adjacent sequences: A147875 A147876 A147877 this_sequence A147879 A147880 A147881
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
James A. Sellers (sellersj(AT)math.psu.edu), Nov 16 2008
|
|
|
Search completed in 0.002 seconds
|
