|
|
A280213
|
|
Number of nX3 0..2 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
|
|
1
|
|
|
0, 26, 158, 886, 4382, 20593, 93326, 410789, 1768582, 7492763, 31338310, 129696524, 531993558, 2165446751, 8755471090, 35192210828, 140712962436, 559989349075, 2219142915606, 8760369870437, 34461931251266, 135134230809249
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = 9*a(n-1) -12*a(n-2) -96*a(n-3) +273*a(n-4) +165*a(n-5) -1237*a(n-6) +1107*a(n-7) +1053*a(n-8) -3215*a(n-9) +2415*a(n-10) +219*a(n-11) -622*a(n-12) -600*a(n-13) +1371*a(n-14) -349*a(n-15) -468*a(n-16) -108*a(n-17) +80*a(n-18) -240*a(n-19) -192*a(n-20) -64*a(n-21) for n>28
|
|
EXAMPLE
|
Some solutions for n=4
..0..1..1. .0..0..1. .0..1..2. .0..0..0. .0..1..2. .0..1..1. .0..1..2
..0..1..0. .0..0..1. .0..2..2. .0..0..1. .1..2..2. .1..1..2. .1..1..2
..0..0..0. .0..1..1. .0..0..2. .0..2..0. .1..2..2. .2..2..1. .1..1..2
..0..0..1. .1..1..2. .0..0..2. .0..0..0. .1..1..1. .2..1..1. .1..1..2
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|