%I A150757
%S A150757 1,2,8,29,132,558,2640,11875,57223,265840,1294971,6133682,30085606,144312174,
               711154466,
%T A150757 3441237378,17013314950,82851670157,410577191021,2008989349008,9973036413246,
               48978069657381,
%U A150757 243459351386625,1199080904886102,5966497845762630,29453453615540568,146676039864165129
%N A150757 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, 1), 
               (1, 0, -1), (1, 0, 1), (1, 1, 0)}
%H A150757 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 A150757 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, 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, 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 A150757 Sequence in context: A150754 A150755 A150756 this_sequence A150758 A009419 
               A000162
%Y A150757 Adjacent sequences: A150754 A150755 A150756 this_sequence A150758 A150759 
               A150760
%K A150757 nonn,walk
%O A150757 0,2
%A A150757 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008