Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A150631
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A150631 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), (0, -1, 1), (0, 1, 0), (1, 0, 1), (1, 1, -1)} +0
1
1, 2, 7, 27, 115, 501, 2266, 10414, 48673, 229899, 1095774, 5259354, 25385793, 123107126, 599282303, 2926781377, 14332693879, 70352155139, 346012928712, 1704732039933, 8411438735489, 41557786740897, 205557391371019, 1017777949837131, 5043845141082382, 25015871533786025, 124158696941193602 (list; graph; listen)
OFFSET

0,2

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[i, -1 + j, k, -1 + n] + aux[i, 1 + 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: A011965 A150629 A150630 this_sequence A150632 A150633 A150634

Adjacent sequences: A150628 A150629 A150630 this_sequence A150632 A150633 A150634

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 December 10 12:37 EST 2009. Contains 170569 sequences.


AT&T Labs Research