%I A148286
%S A148286 1,1,2,5,12,35,101,305,998,3192,10721,37044,126994,452386,1619673,5826276,
21492264,79114692,
%T A148286 294519731,1111169430,4186163252,15968539928,61242924850,235275484768,
913138496950,
%U A148286 3549546890306,13857948020131,54467713887561,214249217663498,847320663811610,
3363260752897618
%N A148286 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), (-1, 0, 1),
(0, 0, -1), (0, 1, -1), (1, 0, 0)}
%H A148286 A. Bostan and M. Kauers, 2008. Automatic Classification of Restricted
Lattice Walks, <a href="http://arxiv.org/abs/0811.2899">ArXiv 0811.2899</
a>.
%t A148286 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, j, k, -1 + n] + aux[i, -1 + j,
1 + k, -1 + n] + aux[i, j, 1 + k, -1 + n] + aux[1 + i, 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}]
%Y A148286 Sequence in context: A000103 A101292 A131267 this_sequence A075202 A075203
A075205
%Y A148286 Adjacent sequences: A148283 A148284 A148285 this_sequence A148287 A148288
A148289
%K A148286 nonn,walk
%O A148286 0,3
%A A148286 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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