|
|
A283945
|
|
Number of nX3 0..1 arrays with no 1 equal to more than three of its horizontal, diagonal and antidiagonal neighbors, with the exception of exactly one element.
|
|
1
|
|
|
0, 2, 87, 900, 8184, 71486, 597042, 4841992, 38481035, 301045074, 2325973337, 17791497852, 134963190603, 1016694067048, 7613544177440, 56723271609684, 420727176381709, 3108419156136654, 22886154154768656, 167982184418042992
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = 14*a(n-1) -53*a(n-2) +66*a(n-3) -370*a(n-4) +772*a(n-5) -629*a(n-6) +2740*a(n-7) -3912*a(n-8) +2424*a(n-9) -8276*a(n-10) +9824*a(n-11) -5152*a(n-12) +8320*a(n-13) -10816*a(n-14) +5632*a(n-15) -1024*a(n-16)
|
|
EXAMPLE
|
Some solutions for n=4
..0..0..0. .1..1..1. .1..1..1. .0..0..0. .1..0..1. .1..1..1. .0..0..0
..1..0..1. .1..0..1. .0..1..1. .1..0..1. .1..0..1. .1..1..0. .1..0..1
..0..1..1. .0..1..0. .1..0..0. .0..1..1. .1..1..1. .0..1..1. .1..1..1
..0..1..1. .0..0..0. .0..0..1. .1..0..0. .0..1..1. .0..0..0. .0..1..0
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|