Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A148473
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A148473 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, 0), (-1, 0, 1), (0, -1, 0), (0, 0, 1), (1, 1, -1)} +0
1
1, 1, 2, 6, 20, 65, 226, 838, 3201, 12386, 48948, 197608, 809096, 3345155, 13980334, 59041103, 251334992, 1076995274, 4645807488, 20164588874, 87973297367, 385580488738, 1697545399851, 7504250584691, 33293669209338, 148208341418642, 661867001127396, 2964446051683526, 13313133410772356 (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[i, j, -1 + k, -1 + n] + aux[i, 1 + j, k, -1 + n] + aux[1 + i, j, -1 + k, -1 + n] + aux[1 + i, 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: A052958 A053730 A005726 this_sequence A000718 A148474 A156831

Adjacent sequences: A148470 A148471 A148472 this_sequence A148474 A148475 A148476

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