%I A148013
%S A148013 1,1,2,3,8,15,49,105,370,849,3095,7414,28588,71396,281514,721183,2905532,
               7606055,31290641,
%T A148013 83451040,347766974,940689178,3969426742,10871603407,46382673907,128408010535,
               552374664184,
%U A148013 1542959571105,6691007154080,18841696947244,82260632828431,233277631001465,
               1024405633824630
%N A148013 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, 1, -1), (1, 0, 0)}
%H A148013 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 A148013 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, 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] + 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 A148013 Sequence in context: A161178 A006882 A080498 this_sequence A133983 A005162 
               A129108
%Y A148013 Adjacent sequences: A148010 A148011 A148012 this_sequence A148014 A148015 
               A148016
%K A148013 nonn,walk
%O A148013 0,3
%A A148013 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008