%I A149178
%S A149178 1,1,4,10,35,124,432,1653,6238,24009,95031,374816,1502701,6081138,24653680,
101007864,415326581,
%T A149178 1714309061,7118874021,29629533128,123789902876,518981830701,2180354287790,
9187801076310,
%U A149178 38803381924060,164201253368975,696395326261535,2958461375328120,12589876811836979
%N A149178 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),
(-1, 0, 1), (0, -1, 1), (1, 1, 0)}
%H A149178 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 A149178 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, 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 A149178 Sequence in context: A149176 A059710 A149177 this_sequence A152916 A108596
A088013
%Y A149178 Adjacent sequences: A149175 A149176 A149177 this_sequence A149179 A149180
A149181
%K A149178 nonn,walk
%O A149178 0,3
%A A149178 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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