Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A148876
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
%I A148876
%S A148876 1,1,3,8,29,107,431,1784,7638,33420,148739,671858,3068426,14150462,65767886,
               307751287,
%T A148876 1448287916,6849461114,32532585554,155097851229,741865738329,3558874732733,
               17117063268783,
%U A148876 82519294654685,398648382352128,1929497558550710,9354947802017698,45427035668583344
%N A148876 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, 1), (1, 0, 0)}
%H A148876 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 A148876 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[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 A148876 Sequence in context: A148874 A022017 A148875 this_sequence A013309 A058378 
               A063839
%Y A148876 Adjacent sequences: A148873 A148874 A148875 this_sequence A148877 A148878 
               A148879
%K A148876 nonn,walk
%O A148876 0,3
%A A148876 Manuel Kauers (manuel(AT)kauers.de), Nov 18 2008

    
page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


AT&T Labs Research