OFFSET
1,1
COMMENTS
See A358046 for further details.
EXAMPLE
a(3) = 128 as, in the first quadrant, the four 3-step SAWs that have the first and last visited lattice point being mutually visible are:
.
X
|
X---. . .---X X
| | | |
X---. X---. X---. X---.---.
.
The sum of square end-to-end displacements of these four walks is 1 + 5 + 5 + 5 = 16. They can be walked in eight different ways on a square lattice thus a(3) = 16 * 8 = 128.
CROSSREFS
KEYWORD
nonn,walk
AUTHOR
Scott R. Shannon, Oct 30 2022
STATUS
approved