Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A148994
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A148994 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, 0, 1), (1, -1, 0), (1, 0, 1), (1, 1, -1)} +0
1
1, 1, 3, 9, 33, 116, 458, 1760, 7255, 29393, 124655, 521829, 2256316, 9664098, 42389957, 184646747, 818911689, 3612785095, 16162919544, 72022055993, 324502937396, 1457666871909, 6606325339738, 29871625322652, 136051924400319, 618569873615481, 2829217786121719, 12923163826023643, 59323860283383890 (list; graph; listen)
OFFSET

0,3

LINKS

A. Bostan and M. Kauers, 2008. Automatic Classification of Restricted Lattice Walks, ArXiv 0811.2899.

MATHEMATICA

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, -1 + k, -1 + n] + aux[-1 + i, 1 + j, k, -1 + n] + aux[1 + i, 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}]

CROSSREFS

Sequence in context: A148991 A148992 A148993 this_sequence A148995 A148996 A148997

Adjacent sequences: A148991 A148992 A148993 this_sequence A148995 A148996 A148997

KEYWORD

nonn,walk

AUTHOR

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 24 23:16 EST 2009. Contains 167481 sequences.


AT&T Labs Research