|
Search: id:A150645
|
|
|
| A150645 |
|
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, 1), (0, 0, 1), (0, 1, 1), (1, -1, 1), (1, 1, -1)} |
|
+0
1
|
|
| 1, 2, 7, 27, 119, 532, 2493, 11751, 56526, 272852, 1330410, 6502103, 31952536, 157280769, 776671738, 3839959233, 19022898390, 94323668554, 468299922839, 2326622294614, 11569292283782, 57559421076093, 286544762335029, 1427071552401897, 7110370388498281, 35438671133831670, 176687791134419279
(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, 1 + j, -1 + k, -1 + n] + aux[i, -1 + j, -1 + k, -1 + n] + aux[i, j, -1 + k, -1 + n] + aux[1 + i, -1 + j, -1 + 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: A150644 A007166 A036783 this_sequence A060017 A058800 A077622
Adjacent sequences: A150642 A150643 A150644 this_sequence A150646 A150647 A150648
|
|
KEYWORD
|
nonn,walk
|
|
AUTHOR
|
Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
|
|
|
Search completed in 0.002 seconds
|
