%I A148160
%S A148160 1,1,2,4,11,31,86,246,736,2276,7240,22690,72285,234747,771123,2566400,
8493635,28334539,
%T A148160 95604553,324278488,1108220193,3778047729,12939669749,44644265673,154504166115,
537300462031,
%U A148160 1866279782528,6502091763142,22768475794159,79893282232247,281289871201986,
989741714280930
%N A148160 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, 1, 1),
(0, 0, -1), (1, 0, 0)}
%H A148160 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 A148160 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, j, 1 +
k, -1 + n] + aux[1 + 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}]
%Y A148160 Sequence in context: A102814 A034770 A002387 this_sequence A148161 A148162
A148163
%Y A148160 Adjacent sequences: A148157 A148158 A148159 this_sequence A148161 A148162
A148163
%K A148160 nonn,walk
%O A148160 0,3
%A A148160 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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