A197052 Number of nX6 0..4 arrays with each element equal to the number its horizontal and vertical zero neighbors.

5, 16, 78, 274, 1132, 4468, 17742, 70616, 281202, 1117442, 4448148, 17693664, 70390082, 280040518, 1114106280, 4432207738, 17633023628, 70149839190, 279079644000, 1110273409628, 4417041071578, 17572471614384, 69909222737482

Offset: 1

Author

R. H. Hardin Oct 09 2011

Keywords

• nonn

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's

Column 6 of A197054

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-1) +7*a(n-2) +9*a(n-3) -15*a(n-4) -38*a(n-5) +45*a(n-6) -16*a(n-7) -91*a(n-9) +117*a(n-10) -63*a(n-11) +52*a(n-12) -19*a(n-13) +5*a(n-14) +8*a(n-15) -10*a(n-16) +4*a(n-17) -4*a(n-18) for n>19