%I A148458
%S A148458 1,1,2,6,18,57,197,707,2636,10048,39101,155433,626277,2558928,10573720,
44116907,185795210,
%T A148458 788396954,3369705436,14493667156,62695350738,272644070203,1191229217515,
5227721322572,
%U A148458 23033834013543,101865871123459,452051235815549,2012436962585313,8985661778362910
%N A148458 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, -1)}
%H A148458 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 A148458 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, 1 + 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 A148458 Sequence in context: A104629 A000957 A125305 this_sequence A148459 A081057
A000137
%Y A148458 Adjacent sequences: A148455 A148456 A148457 this_sequence A148459 A148460
A148461
%K A148458 nonn,walk
%O A148458 0,3
%A A148458 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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