|
|
A253509
|
|
Number of (n+2)X(7+2) 0..1 arrays with every 2X2 and 3X3 subblock diagonal maximum minus antidiagonal minimum nondecreasing horizontally and vertically
|
|
1
|
|
|
1500, 3088, 5692, 10236, 16592, 25988, 38564, 55576, 77680, 106248, 142556, 188308, 245396, 316036, 402740, 508348, 636044, 789376, 972276, 1189080, 1444548, 1743884, 2092756, 2497316, 2964220, 3500648, 4114324, 4813536, 5607156, 6504660
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = (1/6)*n^5 + (11/6)*n^4 + (97/6)*n^3 + (3661/6)*n^2 - (1501/3)*n - 980 for n>12
|
|
EXAMPLE
|
Some solutions for n=4
..1..1..1..1..1..1..1..1..0....0..1..1..1..1..1..1..1..1
..1..1..1..1..1..1..1..1..0....1..1..1..1..1..1..1..1..0
..1..1..1..1..1..1..0..0..0....1..1..1..1..1..1..1..1..0
..1..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..0..0
..1..1..1..1..0..0..0..0..0....1..1..1..1..1..0..1..0..1
..1..1..1..0..0..1..1..1..1....0..0..0..0..0..0..1..0..1
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|