OFFSET
1,3
COMMENTS
From J. Volkmar Schmidt, Oct 18 2023: (Start)
Proof of a(n) = 14576*n^2 - 77924*n + 99292 for n>4 follows proof scheme from David A. Corneth for A186864.
Distribution matrix of surrounding rectangles for 6-step walks is:
[0 0 0 0 0 2]
[0 0 96 576 448 124]
[0 96 1856 2272 1064 224]
[0 576 2272 1552 560 104]
[0 448 1064 560 168 28]
[2 124 224 104 28 4]
(End)
LINKS
Index entries for linear recurrences with constant coefficients, signature (3, -3, 1).
FORMULA
Empirical: a(n) = 14576*n^2 - 77924*n + 99292 for n>4.
EXAMPLE
Some solutions for 3X3
..0..2..0....0..4..0....0..4..3....0..0..0....0..2..1....3..2..0....0..4..5
..1..3..4....2..3..5....6..5..2....1..2..6....0..4..3....4..0..1....3..0..6
..6..5..0....1..6..0....0..0..1....3..4..5....0..5..6....6..5..0....1..2..0
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 27 2011
STATUS
approved