%I A149302
%S A149302 1,1,4,11,46,172,750,3120,14087,61571,284436,1281379,6008651,27633271,
130944600,611154458,
%T A149302 2918673524,13771848825,66164267793,314806106581,1519581215764,7277197766203,
35261251918970,
%U A149302 169741515939425,825046304792297,3988381669094450,19436472354360319,94285252643418217
%N A149302 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, -1, 1), (1, 1, -1), (1, 1, 0)}
%H A149302 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 A149302 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, 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, k, -1 + n]]; Table[Sum[aux[i,
j, k, n], {i, 0, n}, {j, 0, n}, {k, 0, n}], {n, 0, 10}]
%Y A149302 Sequence in context: A149299 A149300 A149301 this_sequence A149303 A053882
A149304
%Y A149302 Adjacent sequences: A149299 A149300 A149301 this_sequence A149303 A149304
A149305
%K A149302 nonn,walk
%O A149302 0,3
%A A149302 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008
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