%I A149175
%S A149175 1,1,4,10,35,117,429,1563,6023,23289,92152,369488,1502119,6160145,25528852,
106682938,448960587,
%T A149175 1901408027,8104762740,34722538926,149465829383,646360473228,2806706370121,
12231645222422,
%U A149175 53492893993153,234717283187637,1032901850100970,4557956790155818,20167098103048672
%N A149175 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, 0),
(0, 0, -1), (1, -1, 0), (1, 1, 0)}
%H A149175 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 A149175 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[-1 +
i, 1 + j, k, -1 + n] + aux[i, j, 1 + k, -1 + n] + aux[1 + i, j, 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 A149175 Sequence in context: A149173 A149174 A030003 this_sequence A149176 A059710
A149177
%Y A149175 Adjacent sequences: A149172 A149173 A149174 this_sequence A149176 A149177
A149178
%K A149175 nonn,walk
%O A149175 0,3
%A A149175 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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