A198483 Number of 2nX4 0..3 arrays with values 0..3 introduced in row major order and each element equal to an even number of horizontal and vertical neighbors

193, 333308, 579476701, 1007486056500, 1751630302786777, 3045410673315147020, 5294796602205290417269, 9205612663330831095993732, 16005016032539421751657150321, 27826560552805542982631002720412

Offset

1,1

Comments

Column 2 of A198485

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 1830*a(n-1) -159372*a(n-2) +792258*a(n-3) +98338987*a(n-4) +2158821756*a(n-5) +5589826848*a(n-6) -27817587324*a(n-7) -4450735463643*a(n-8) +20799919432638*a(n-9) -18431744997780*a(n-10) -20774261461158*a(n-11) +22876792454961*a(n-12)

Example

Some solutions for n=3
..0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0....0..0..0..1
..0..1..2..0....0..1..0..0....0..1..2..0....0..1..2..0....0..1..0..0
..0..0..3..0....0..0..2..0....0..0..0..0....0..0..1..0....0..0..1..0
..1..0..0..0....1..0..0..0....1..2..3..1....2..0..3..0....1..0..0..0
..2..1..2..3....2..1..2..3....2..0..1..3....1..0..0..0....0..2..1..3
..3..2..3..0....3..2..3..1....3..1..2..1....0..1..2..1....1..0..3..2

Crossrefs

Sequence in context: A120851 A302332 A344147 * A115735 A023743 A025333

Adjacent sequences: A198480 A198481 A198482 * A198484 A198485 A198486

Keyword

nonn

Author

R. H. Hardin Oct 25 2011

Status

approved