A198150 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,0,1,1 for x=0,1,2,3,4

2, 12, 54, 240, 1170, 5330, 24689, 116890, 549479, 2578328, 12131698, 57065922, 268256602, 1261383897, 5931754425, 27891320698, 131147135601, 616682910805, 2899744304684, 13635001788168, 64114012351029, 301474577118884

Offset

1,1

Comments

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

Column 3 of A198155

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) +38*a(n-3) +40*a(n-4) +21*a(n-5) -127*a(n-6) -313*a(n-7) -143*a(n-8) +681*a(n-9) +1988*a(n-10) +1587*a(n-11) -1232*a(n-12) -4569*a(n-13) -5344*a(n-14) -992*a(n-15) +3626*a(n-16) +4576*a(n-17) +2900*a(n-18) +162*a(n-19) -844*a(n-20) -954*a(n-21) -250*a(n-22) +190*a(n-23) +34*a(n-24) -a(n-25)

Example

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

Crossrefs

Sequence in context: A111642 A145766 A181765 * A122676 A038175 A181541

Adjacent sequences: A198147 A198148 A198149 * A198151 A198152 A198153

Keyword

nonn

Author

R. H. Hardin Oct 21 2011

Status

approved