A202329 Number of (n+1)X(n+1) binary arrays with consecutive windows of two bits considered as a binary number nondecreasing in every row and column

16, 48, 162, 576, 2102, 7790, 29174, 110112, 418134, 1595622, 6113746, 23505358, 90633802, 350351642, 1357278302, 5268292832, 20483876822, 79765662902, 311038321442, 1214362277702, 4746455801882, 18570960418922, 72728638093802

Offset

1,1

Comments

Diagonal of A202335

Links

R. H. Hardin, Table of n, a(n) for n = 1..71

Formula

Empirical: (n+1)*(27*n-40)*a(n) = (135*n^2-123*n-100)*a(n-1) - 2*(54*n^2-63*n-10)*a(n-2) - 8*(2*n-5)*a(n-3). - Vaclav Kotesovec, Oct 19 2012

Another recurrence (empirical): (n+1)*(9*n^2-19*n+8)*a(n) = (45*n^3-68*n^2-13*n+20)*a(n-1) - 2*(2*n-3)*(9*n^2-n-2)*a(n-2). - Vaclav Kotesovec, Oct 26 2012

Example

Some solutions for n=5
..0..0..0..0..0..1....0..0..0..0..1..0....0..0..0..0..1..0....0..0..0..0..0..1
..0..0..0..0..0..1....0..0..0..0..1..1....0..0..0..0..1..0....0..0..0..0..0..1
..0..0..0..0..0..1....0..0..0..0..1..1....0..0..1..1..1..1....0..0..0..0..0..1
..0..0..0..0..0..1....0..0..1..1..1..1....0..0..1..1..1..1....0..0..0..0..1..1
..0..0..0..1..1..1....0..1..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..1..1..1....0..0..1..1..1..1....1..1..1..1..1..1

Crossrefs

Sequence in context: A235541 A109098 A223395 * A223599 A223692 A165115

Adjacent sequences: A202326 A202327 A202328 * A202330 A202331 A202332

Keyword

nonn

Author

R. H. Hardin Dec 17 2011

Status

approved