A197103 Half the number of nX2 0..3 arrays with no element equal to the average of its horizontal and vertical neighbors

6, 78, 1015, 13526, 181032, 2421376, 32393085, 433365018, 5797636941, 77561969587, 1037640271854, 13881766929498, 185713161140663, 2484509257009467, 33238281011983990, 444668628838107492

Offset

1,1

Comments

Column 2 of A197109

Links

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

Formula

Empirical: a(n) = 13*a(n-1) +5*a(n-2) +30*a(n-3) -377*a(n-4) -258*a(n-5) +874*a(n-6) +1758*a(n-7) +685*a(n-8) -2995*a(n-9) -3798*a(n-10) -1113*a(n-11) +2557*a(n-12) +3786*a(n-13) +1955*a(n-14) -639*a(n-15) -1523*a(n-16) -683*a(n-17) +14*a(n-18) +254*a(n-19) +36*a(n-20)

Example

Some solutions for 4X4
..1..2....0..1....0..1....1..1....0..1....1..2....1..3....1..3....1..1....1..3
..2..0....3..3....0..3....3..3....1..0....1..0....2..3....1..0....3..3....3..0
..0..0....3..3....1..3....3..0....0..3....3..3....1..1....3..1....1..0....1..0
..1..1....1..0....2..0....0..2....2..1....1..0....3..3....1..2....1..2....1..3

Crossrefs

Sequence in context: A069670 A074112 A372181 * A345360 A208473 A379025

Adjacent sequences: A197100 A197101 A197102 * A197104 A197105 A197106

Keyword

nonn

Author

R. H. Hardin Oct 10 2011

Status

approved