%I A148873
%S A148873 1,1,3,8,29,97,354,1300,5129,19092,77071,302902,1224459,4889175,20230479,
               81922468,339766702,
%T A148873 1398618423,5853729563,24226447913,102042112312,426606797100,1802017383786,
               7573988021017,
%U A148873 32177115099918,135889802109788,578695267283061,2456508103944632,10495089623826787
%N A148873 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, -1, 1), 
               (-1, 1, 1), (0, 1, -1), (1, 0, 1)}
%H A148873 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 A148873 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[i, -1 
               + j, 1 + k, -1 + n] + aux[1 + i, -1 + j, -1 + k, -1 + n] + aux[1 
               + i, 1 + 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 A148873 Sequence in context: A148870 A148871 A148872 this_sequence A148874 A022017 
               A148875
%Y A148873 Adjacent sequences: A148870 A148871 A148872 this_sequence A148874 A148875 
               A148876
%K A148873 nonn,walk
%O A148873 0,3
%A A148873 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008