A198702 Number of nX2 0..4 arrays with values 0..4 introduced in row major order and each element equal to at least one horizontal or vertical neighbor

1, 3, 14, 76, 488, 3508, 27422, 227045, 1950662, 17146596, 152812056, 1373072354, 12397256874, 112250461201, 1018054465392, 9242194131044, 83950882529364, 762814946316712, 6932614771099750, 63012101072493525, 572768961745981914

Offset

1,2

Comments

Column 2 of A198708

Links

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

Formula

Empirical: a(n) = 17*a(n-1) -80*a(n-2) +37*a(n-3) +349*a(n-4) -60*a(n-5) -729*a(n-6) -553*a(n-7) +572*a(n-8) +783*a(n-9) +139*a(n-10) -304*a(n-11) -170*a(n-12)

Example

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

Crossrefs

Sequence in context: A364477 A364758 A353253 * A198621 A198649 A198656

Adjacent sequences: A198699 A198700 A198701 * A198703 A198704 A198705

Keyword

nonn

Author

R. H. Hardin Oct 29 2011

Status

approved