|
Search: id:A150389
|
|
|
| A150389 |
|
Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (0, 1, -1), (1, 0, 1), (1, 1, 1)} |
|
+0
1
|
|
| 1, 2, 7, 24, 86, 324, 1224, 4667, 18103, 70228, 273857, 1074849, 4222120, 16626466, 65686791, 259694763, 1028088033, 4077689559, 16181304904, 64263458424, 255518428334, 1016318151113, 4044527578019, 16107719555495, 64166416507816, 255705521318870, 1019510693666675, 4065587878831178
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
LINKS
|
A. Bostan and M. Kauers, 2008. Automatic Classification of Restricted Lattice Walks, ArXiv 0811.2899.
|
|
MATHEMATICA
|
aux[i_Integer, j_Integer, k_Integer, n_Integer] := Which[Min[i, j, k, n] < 0 || Max[i, j, k] > n, 0, n == 0, KroneckerDelta[i, j, k, n], True, aux[i, j, k, n] = aux[-1 + i, -1 + j, -1 + k, -1 + n] + aux[-1 + i, j, -1 + k, -1 + n] + aux[i, -1 + j, 1 + k, -1 + n] + aux[1 + i, 1 + j, k, -1 + n]]; Table[Sum[aux[i, j, k, n], {i, 0, n}, {j, 0, n}, {k, 0, n}], {n, 0, 10}]
|
|
CROSSREFS
|
Sequence in context: A014300 A128086 A131824 this_sequence A104625 A151293 A122446
Adjacent sequences: A150386 A150387 A150388 this_sequence A150390 A150391 A150392
|
|
KEYWORD
|
nonn,walk
|
|
AUTHOR
|
Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
|
|
|
Search completed in 0.002 seconds
|
