|
|
A202332
|
|
Number of (n+1) X 6 binary arrays with consecutive windows of two bits considered as a binary number nondecreasing in every row and column.
|
|
1
|
|
|
64, 191, 478, 1052, 2102, 3896, 6800, 11299, 18020, 27757, 41498, 60454, 86090, 120158, 164732, 222245, 295528, 387851, 502966, 645152, 819262, 1030772, 1285832, 1591319, 1954892, 2385049, 2891186, 3483658, 4173842, 4974202, 5898356, 6961145
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = (1/360)*n^6 + (1/12)*n^5 + (17/18)*n^4 + (16/3)*n^3 + (5779/360)*n^2 + (295/12)*n + 17.
G.f.: x*(64 - 257*x + 485*x^2 - 523*x^3 + 331*x^4 - 115*x^5 + 17*x^6) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>7.
(End)
|
|
EXAMPLE
|
Some solutions for n=5:
..0..0..0..1..1..1....0..0..0..0..0..0....0..0..0..0..1..0....0..0..0..0..1..0
..1..1..1..1..1..1....0..0..0..0..0..0....0..0..0..0..1..0....0..0..0..0..1..0
..1..1..1..1..1..1....0..0..0..0..0..1....0..0..0..1..1..1....0..0..0..0..1..1
..1..1..1..1..1..1....0..0..0..0..0..1....1..1..1..1..1..1....0..0..0..0..1..1
..1..1..1..1..1..1....0..0..0..1..1..1....1..1..1..1..1..1....1..1..1..1..1..1
..1..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..1....0..0..1..1..1..1
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|