A198719 Number of nX4 0..6 arrays with values 0..6 introduced in row major order and no element equal to any horizontal or vertical neighbor

5, 499, 232841, 173549032, 141168480719, 116492275674072, 96356630422085931, 79732515488691835557, 65980773070548173552412, 54601426682639992758644080, 45184694908666112938858073903, 37392013011256643009627621268829

Offset

1,1

Comments

Column 4 of A198723

Links

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

Formula

Empirical: a(n) = 1081*a(n-1) -231028*a(n-2) +18466747*a(n-3) -729356901*a(n-4) +16017483310*a(n-5) -207602672167*a(n-6) +1633653422655*a(n-7) -7862297151184*a(n-8) +22902587520657*a(n-9) -39383752489643*a(n-10) +38480449661142*a(n-11) -19517387256516*a(n-12) +3939042601848*a(n-13)

Example

Some solutions with all values 0 to 6 for n=5
..0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1....0..1..0..1
..1..0..1..0....1..0..1..0....1..0..1..0....1..0..1..0....1..0..1..0
..0..2..0..1....2..1..0..1....2..3..0..1....2..3..0..1....2..3..0..1
..3..4..1..4....1..0..3..4....4..5..6..3....4..5..4..5....1..0..4..2
..5..6..4..0....5..4..0..6....6..0..4..0....0..4..6..1....4..5..3..6

Crossrefs

Sequence in context: A152513 A012822 A124358 * A198910 A207866 A013305

Adjacent sequences: A198716 A198717 A198718 * A198720 A198721 A198722

Keyword

nonn

Author

R. H. Hardin Oct 29 2011

Status

approved