|
Search: id:A000356
|
|
|
| A000356 |
|
Number of Hamiltonian rooted maps with 2n nodes: (2n)!(2n+1)!/(n!^2*(n+1)!(n+2)!). (Formerly M3978 N1647)
|
|
+0 7
|
|
| 1, 5, 35, 294, 2772, 28314, 306735, 3476330, 40831076, 493684828, 6114096716, 77266057400, 993420738000, 12964140630900, 171393565105575, 2291968851019650, 30961684478686500, 422056646314726500
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
REFERENCES
|
W. T. Tutte, A census of Hamiltonian polygons, Canad. J. Math., 14 (1962), 402-417.
W. T. Tutte, On the enumeration of four-colored maps, SIAM J. Appl. Math., 17 (1969), 454-460.
|
|
LINKS
|
R. K. Guy, Catwalks, Sandsteps and Pascal Pyramids, J. Integer Seqs., Vol. 3 (2000), #00.1.6
|
|
MAPLE
|
f:=n->(2*n)!*(2*n+2)!/(2*n!*(n+1)!*(n+1)!*(n+2)!);
hypergeom([ 1, 5/2, 3/2 ], [ 3, 4 ], 16*x);
|
|
CROSSREFS
|
Equals A005568/2.
Image of A001700 under the "little Hankel" transform (see A056220 for definition) - John W. Layman (layman(AT)math.vt.edu), Aug 22 2000
Fourth row of array A102539.
Column of array A073165.
Sequence in context: A138233 A002294 A051406 this_sequence A027392 A109253 A052797
Adjacent sequences: A000353 A000354 A000355 this_sequence A000357 A000358 A000359
|
|
KEYWORD
|
easy,nonn,nice
|
|
AUTHOR
|
njas, Simon Plouffe (plouffe(AT)math.uqam.ca)
|
|
|
Search completed in 0.002 seconds
|