%I A148875
%S A148875 1,1,3,8,29,104,405,1634,6788,28922,125559,554058,2474920,11188064,51025586,
               234609810,
%T A148875 1086430868,5061096381,23702973326,111544459533,527097647852,2500077258967,
               11898645626830,
%U A148875 56798990784424,271874618573959,1304627798728260,6274476702322705,30238642580810987
%N A148875 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, 0, 1), (-1, 1, 1), 
               (0, 1, -1), (1, -1, 0), (1, 0, 0)}
%H A148875 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 A148875 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, k, -1 + n] + aux[i, -1 + j, 1 + k, -1 + n] + aux[1 + i, -1 + 
               j, -1 + k, -1 + n] + aux[1 + i, 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 A148875 Sequence in context: A148873 A148874 A022017 this_sequence A148876 A013309 
               A058378
%Y A148875 Adjacent sequences: A148872 A148873 A148874 this_sequence A148876 A148877 
               A148878
%K A148875 nonn,walk
%O A148875 0,3
%A A148875 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008