%I A148100
%S A148100 1,1,2,4,10,26,76,239,753,2540,8572,30128,106501,387844,1422789,5316121,
               20099588,76671429,
%T A148100 296355338,1151184226,4524804463,17853802855,71134139857,284557313732,
               1146559570375,
%U A148100 4641910594671,18885060480277,77240337339152,316960064504831,1307542974531887,
               5407643110588584
%N A148100 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, 0, 1), 
               (0, -1, 1), (0, 1, -1), (1, 0, 0)}
%H A148100 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 A148100 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, -1 + j, 
               1 + k, -1 + n] + aux[i, 1 + j, -1 + k, -1 + n] + aux[1 + i, 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 A148100 Sequence in context: A007580 A000085 A047653 this_sequence A149815 A149816 
               A149817
%Y A148100 Adjacent sequences: A148097 A148098 A148099 this_sequence A148101 A148102 
               A148103
%K A148100 nonn,walk
%O A148100 0,3
%A A148100 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008