A196585 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,2,0,1,4 for x=0,1,2,3,4

2, 20, 120, 698, 4078, 24032, 141460, 830652, 4886324, 28734972, 168979540, 993659990, 5842982750, 34359849144, 202051334982, 1188148848850, 6986829817634, 41085617221494, 241601571059434, 1420723058603468

Offset

1,1

Comments

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

Column 3 of A196590

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +6*a(n-2) +39*a(n-3) +104*a(n-4) +306*a(n-5) -248*a(n-6) +121*a(n-7) -629*a(n-8) +185*a(n-9) -1768*a(n-10) -3604*a(n-11) -297*a(n-12) -1760*a(n-13) -520*a(n-14) +1300*a(n-15) -226*a(n-16) -1807*a(n-17) -90*a(n-18) +2286*a(n-19) +2319*a(n-20) +634*a(n-21) -1588*a(n-22) -995*a(n-23) +386*a(n-24) +236*a(n-25) -56*a(n-26) -16*a(n-27)

Example

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

Crossrefs

Sequence in context: A219837 A219759 A196797 * A197042 A350549 A062189

Adjacent sequences: A196582 A196583 A196584 * A196586 A196587 A196588

Keyword

nonn

Author

R. H. Hardin Oct 04 2011

Status

approved