%I A149268
%S A149268 1,1,4,11,40,147,537,2067,8090,31759,127226,512728,2085944,8530109,35108141,
145290427,
%T A149268 603473533,2516899058,10535376447,44235546052,186238821286,786137476704,
3326533736676,
%U A149268 14104293872530,59921599051958,255045546995888,1087354970834820,4643011158411006
%N A149268 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), (-1, 0, 1),
(-1, 1, 1), (0, -1, 1), (1, 1, 0)}
%H A149268 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 A149268 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, k, -1 + n] + aux[i, 1
+ j, -1 + k, -1 + n] + aux[1 + i, -1 + j, -1 + k, -1 + n] + aux[1
+ 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}]
%Y A149268 Sequence in context: A149265 A149266 A149267 this_sequence A077236 A152532
A121096
%Y A149268 Adjacent sequences: A149265 A149266 A149267 this_sequence A149269 A149270
A149271
%K A149268 nonn,walk
%O A149268 0,3
%A A149268 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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