%I A148107
%S A148107 1,1,2,4,10,27,84,265,892,3078,10917,39683,147762,559640,2154331,8416964,
33261595,132862775,
%T A148107 536061253,2182072592,8952086612,37000546739,153950290800,644361566782,
2712078227312,
%U A148107 11474353274885,48776461977010,208261335853889,892909478125003,3842953777938297
%N A148107 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, 0),
(0, 0, 1), (1, -1, 1), (1, 0, -1)}
%H A148107 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 A148107 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, 1 + k, -1 + n] + aux[-1 +
i, 1 + j, -1 + k, -1 + n] + aux[i, j, -1 + k, -1 + n] + aux[1 + i,
-1 + j, 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 A148107 Sequence in context: A099950 A121690 A138356 this_sequence A148108 A057786
A007776
%Y A148107 Adjacent sequences: A148104 A148105 A148106 this_sequence A148108 A148109
A148110
%K A148107 nonn,walk
%O A148107 0,3
%A A148107 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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