|
|
A279704
|
|
Number of n X 3 0..1 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors and with new values introduced in order 0 sequentially upwards.
|
|
1
|
|
|
1, 3, 11, 42, 161, 617, 2364, 9057, 34699, 132938, 509309, 1951253, 7475596, 28640333, 109726191, 420380482, 1610552121, 6170310577, 23639553244, 90567317577, 346979442819, 1329339732698, 5092936084549, 19511940644893
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = 5*a(n-1) - 5*a(n-2) + 2*a(n-3).
Empirical g.f.: x*(1 - x)^2 / (1 - 5*x + 5*x^2 - 2*x^3). - Colin Barker, Feb 11 2019
|
|
EXAMPLE
|
Some solutions for n=4:
..0..1..0. .0..1..0. .0..1..0. .0..1..0. .0..1..1. .0..1..0. .0..1..1
..0..1..0. .1..0..1. .0..1..0. .0..1..1. .0..0..1. .0..1..0. .0..0..1
..1..0..1. .1..0..1. .0..0..1. .1..0..0. .1..0..0. .1..0..0. .0..1..1
..1..0..1. .0..1..0. .1..0..1. .0..1..0. .1..1..0. .1..1..0. .0..0..1
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|