|
|
A300534
|
|
Number of nX3 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
|
|
1
|
|
|
1, 5, 12, 36, 122, 429, 1585, 5755, 21084, 77823, 286982, 1060139, 3917406, 14477542, 53517820, 197837108, 731366681, 2703796615, 9995728589, 36953720967, 136616452365, 505066168745, 1867213688572, 6903032086068, 25520304669843
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = 2*a(n-1) +7*a(n-2) +6*a(n-3) -21*a(n-4) -36*a(n-5) -26*a(n-6) +4*a(n-7) +62*a(n-8) +82*a(n-9) +18*a(n-10) -52*a(n-11) -42*a(n-12) +72*a(n-13) +38*a(n-14) +12*a(n-15) -25*a(n-16) -16*a(n-17) -4*a(n-18) -6*a(n-19) +8*a(n-20) -4*a(n-21) +2*a(n-22) for n>24
|
|
EXAMPLE
|
Some solutions for n=5
..0..0..0. .0..1..1. .0..0..1. .0..0..1. .0..0..0. .0..0..1. .0..0..0
..0..1..0. .1..0..1. .0..1..1. .0..1..1. .0..1..0. .0..1..1. .0..1..0
..0..0..0. .1..1..0. .0..0..0. .1..1..1. .0..0..0. .1..0..1. .0..0..0
..0..1..1. .0..1..1. .0..0..1. .0..0..0. .0..1..0. .1..1..1. .1..1..1
..1..1..1. .1..1..1. .0..1..1. .0..0..1. .0..0..0. .0..1..1. .1..1..0
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|