|
|
A193480
|
|
Number of n X n symmetric 0..1 arrays with each element equal to the product mod 2 of two of its horizontal and vertical neighbors
|
|
1
|
|
|
0, 2, 4, 26, 240, 4063, 110576, 5046694, 390350577, 51445991632, 11496127271424, 4348804724288989, 2784306483759192151, 3019459887601073667024, 5548682373331641079067391, 17274304412990968236505863156
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
EXAMPLE
|
Some solutions for 4X4
..0..0..1..1....1..1..1..1....1..1..0..0....1..1..1..1....1..1..1..0
..0..0..1..1....1..0..0..1....1..1..1..1....1..1..1..1....1..1..1..0
..1..1..1..0....1..0..0..1....0..1..1..1....1..1..1..1....1..1..1..1
..1..1..0..0....1..1..1..1....0..1..1..1....1..1..1..1....0..0..1..1
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|