A231746 T(n,k)=Number of nXk 0..3 arrays with no element less than a strict majority of its horizontal and vertical neighbors.

4, 4, 4, 16, 84, 16, 50, 318, 318, 50, 144, 1328, 4430, 1328, 144, 422, 6064, 60806, 60806, 6064, 422, 1268, 26918, 784076, 2154900, 784076, 26918, 1268, 3823, 116909, 9945132, 71742015, 71742015, 9945132, 116909, 3823, 11472, 511264, 126926437

Offset: 1

Author

R. H. Hardin, Nov 13 2013

Keywords

• nonn
• tabl

Comments

Table starts

....4......4.........16............50..............144..................422

....4.....84........318..........1328.............6064................26918

...16....318.......4430.........60806...........784076..............9945132

...50...1328......60806.......2154900.........71742015...........2426463539

..144...6064.....784076......71742015.......6425495277.........598711367728

..422..26918....9945132....2426463539.....598711367728......155985773478611

.1268.116909..126926437...82701946547...56006640316980....40539474933206048

.3823.511264.1625269595.2814528154294.5220406326242670.10471241201508754882

Examples

			Some solutions for n=3 k=4
..0..2..0..0....3..1..1..2....0..2..1..0....0..0..2..2....1..1..3..1
..0..3..0..3....3..1..0..0....0..0..0..0....1..0..0..3....3..1..1..1
..0..1..0..0....3..1..0..0....0..3..3..1....3..1..0..0....0..0..0..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..111

Crossrefs

Column 1 is A203094 for n>1

Formula

Empirical for column k:

k=1: a(n) = 4*a(n-1) -6*a(n-2) +10*a(n-3) -5*a(n-4) +6*a(n-5) -a(n-6) +a(n-7) for n>8

k=2: [order 19] for n>20

k=3: [order 87] for n>88