# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a148389 Showing 1-1 of 1 %I A148389 #4 Jan 01 2024 00:52:28 %S A148389 1,1,2,5,16,51,175,603,2179,7966,30115,115175,447599,1754566,6960211, %T A148389 27838776,112401002,457156790,1872092533,7709515518,31925277406, %U A148389 132858964434,555535209096,2332992606313,9836786434533,41626228814418,176751460040269,752917025247036,3216949479854651 %N A148389 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), (0, 1, -1), (1, 0, 0), (1, 1, -1)}. %H A148389 A. Bostan and M. Kauers, 2008. Automatic Classification of Restricted Lattice Walks, ArXiv 0811.2899. %t A148389 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, -1 + j, 1 + k, -1 + n] + aux[-1 + i, j, 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, k, -1 + n]]; Table[Sum[aux[i, j, k, n], {i, 0, n}, {j, 0, n}, {k, 0, n}], {n, 0, 10}] %K A148389 nonn,walk %O A148389 0,3 %A A148389 _Manuel Kauers_, Nov 18 2008 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE