A205748 Number of (n+1)X4 0..2 arrays with every 2X2 subblock having the same number of equal edges as its horizontal neighbors and a different number from its vertical neighbors, and new values 0..2 introduced in row major order

175, 1074, 8926, 63838, 507035, 3797920, 29561841, 224378004, 1731531322, 13218640560, 101623450551, 777700795868, 5969371745835, 45729619667448, 350767461372176, 2688316203091256, 20614685172668943, 158022715770190920

Offset

1,1

Comments

Column 3 of A205753

Links

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

Formula

Empirical: a(n) = 54*a(n-2) +120*a(n-3) -417*a(n-4) -1856*a(n-5) -569*a(n-6) +11608*a(n-7) +19462*a(n-8) -37804*a(n-9) -97827*a(n-10) +69396*a(n-11) +253384*a(n-12) -49104*a(n-13) -366356*a(n-14) -46288*a(n-15) +244448*a(n-16) +127408*a(n-17) +41532*a(n-18) -58496*a(n-19) -119360*a(n-20) -44544*a(n-21) for n>22

Example

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

Crossrefs

Sequence in context: A109836 A332047 A186211 * A352109 A349674 A205470

Adjacent sequences: A205745 A205746 A205747 * A205749 A205750 A205751

Keyword

nonn

Author

R. H. Hardin Jan 30 2012

Status

approved