|
Search: id:A099114
|
|
|
| A099114 |
|
Number of rhombus tilings of a hexagon with side lengths 2n,2n+2,2n,2n,2n+2,2n which contain the rhombus above and next to the center of the hexagon. |
|
+0
1
|
|
| 19, 2252052, 125575149020464, 3624877924928635307525440, 55204136490632334691332479792745796875, 446207680704793917097310140821019734826847707500000000
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
M. Fulmek and C. Krattenthaler, [math/9909038] The number of rhombus tilings of a symmetric hexagon which contain a fixed rhombus on the symmetry axis, II
|
|
PROGRAM
|
(PARI) a(n)=(1/3-(10*n+2)/(6*n+3)*binomial(2*n, n)^3/binomial(6*n+2, 3*n+1))*prod(i=1, 2*n, prod(j=1, 2*n+2, prod(k=1, 2*n, (i+j+k-1)/(i+j+k-2))))
|
|
CROSSREFS
|
Cf. A099112-A099117, A008793.
Sequence in context: A013764 A078353 A070632 this_sequence A013810 A145308 A087515
Adjacent sequences: A099111 A099112 A099113 this_sequence A099115 A099116 A099117
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Ralf Stephan, Oct 01 2004
|
|
|
Search completed in 0.002 seconds
|
