%I A149306
%S A149306 1,1,4,11,48,157,711,2559,11846,45183,212143,840277,3984616,16205687,77410374,
321065635,
%T A149306 1542228908,6494244945,31332380867,133546094665,646603376846,2783426236771,
13516256002852,
%U A149306 58666741189805,285582656349044,1248296193322585,6089197321956135,26777517944746803
%N A149306 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), (1, 0, -1), (1, 0, 1)}
%H A149306 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 A149306 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, 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 A149306 Sequence in context: A053882 A149304 A149305 this_sequence A149307 A149308
A149309
%Y A149306 Adjacent sequences: A149303 A149304 A149305 this_sequence A149307 A149308
A149309
%K A149306 nonn,walk
%O A149306 0,3
%A A149306 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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