editing

approved

R. H. Hardin, <a href="/A232061/b232061.txt">Table of n, a(n) for n = 1..210</a>

allocated for R. H. Hardin

Number of nX4 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or vertically, with no adjacent values equal

6, 30, 130, 534, 2230, 9310, 38870, 162278, 677510, 2828606, 11809446, 49304494, 205846518, 859410282, 3588042398, 14980095674, 62541977366, 261113080850, 1090148470882, 4551375536978, 19002016543538, 79333517919430

1,1

Column 4 of A232065

Empirical: a(n) = 4*a(n-1) +a(n-2) -4*a(n-4) -3*a(n-5) +a(n-7) +3*a(n-8) -a(n-11)

Some solutions for n=7

..1..0..1..2....0..1..0..1....1..2..1..0....2..0..1..2....2..1..2..1

..2..1..0..1....1..2..1..2....0..1..0..2....0..2..0..1....1..2..1..0

..1..2..1..0....2..1..2..1....1..0..2..1....1..0..1..0....2..1..2..1

..2..0..2..1....1..0..1..2....2..1..0..2....2..1..2..1....1..2..1..0

..0..1..0..2....2..1..0..1....1..2..1..0....0..2..1..2....2..1..2..1

..1..2..1..0....1..2..1..2....2..1..2..1....1..0..2..1....1..2..1..0

..2..1..0..2....0..1..2..1....1..0..1..2....2..1..0..2....0..1..2..1

allocated

nonn

R. H. Hardin, Nov 17 2013

approved

editing

allocated for R. H. Hardin

allocated

approved