%I A149855
%S A149855 1,2,5,13,37,119,397,1364,4690,16567,60099,221639,824168,3076794,11626300,
               44410611,171024300,
%T A149855 661133266,2566409626,10027307231,39409100079,155553063846,615628813008,
               2444688640372,
%U A149855 9747085883927,39001498700419,156466842555659,629063961684359,2535651643941736
%N A149855 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, 0), 
               (-1, 1, 0), (0, 0, 1), (1, 0, 0)}
%H A149855 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 A149855 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[i, j, -1 
               + k, -1 + n] + aux[1 + i, -1 + j, k, -1 + n] + aux[1 + i, 1 + j, 
               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 A149855 Sequence in context: A053732 A119495 A148301 this_sequence A149856 A064384 
               A148302
%Y A149855 Adjacent sequences: A149852 A149853 A149854 this_sequence A149856 A149857 
               A149858
%K A149855 nonn,walk
%O A149855 0,2
%A A149855 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008