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A034165
Number of 'zig-zag' self-avoiding walks on an n X n lattice from a corner to opposite one.
1
1, 2, 2, 4, 10, 36, 188, 1582, 20576, 388592, 10461898, 408377408, 23652253982, 2052824036762, 265634749049320, 50828371798067240, 14332652975511249270, 5965063285700860583374, 3673747085941764271303790, 3352654279654465148964378096
OFFSET
1,2
COMMENTS
A 'zig-zag' walk does not contain 2 consecutive steps in the same direction.
LINKS
Eric Weisstein's World of Mathematics, Self-avoiding walk.
EXAMPLE
a(4)=4 because of the following paths:
A._......A......A.._.......A_
...|_....|_.....|_|.|_......_|
.....|_....|_........_|....|_..._
.......|.....|_.....|_.......|_|.|
.......B.......B......B..........B
CROSSREFS
Cf. A034166.
Sequence in context: A112556 A254400 A054100 * A006181 A366425 A322924
KEYWORD
nonn,walk
AUTHOR
EXTENSIONS
a(7)-a(11) computed by David W. Wilson
a(12)-a(13) computed by Luca Petrone, Dec 31 2015
a(14)-a(20) from Andrew Howroyd, Jan 15 2018
STATUS
approved