A210398 Number of (n+1) X 3 0..3 arrays with every 2 X 2 subblock having one or three distinct values, and new values 0..3 introduced in row major order.

59, 1316, 29647, 668468, 15072359, 339846892, 7662761615, 172777559876, 3895734547831, 87839807902364, 1980584600286431, 44657604024550516, 1006925731385059271, 22703847433641032396, 511919272915004314159

Offset

1,1

Comments

Column 2 of A210404.

Links

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

Formula

Empirical: a(n) = 28*a(n-1) - 123*a(n-2) - 20*a(n-3) + 500*a(n-4) - 384*a(n-5).

Empirical g.f.: x*(59 - 336*x + 56*x^2 + 1400*x^3 - 1344*x^4) / ((1 - x)*(1 + 2*x)*(1 - 29*x + 154*x^2 - 192*x^3)). - Colin Barker, Jul 15 2018

Example

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

Crossrefs

Cf. A210404.

Sequence in context: A245941 A248620 A374450 * A278366 A134652 A017775

Adjacent sequences: A210395 A210396 A210397 * A210399 A210400 A210401

Keyword

nonn

Author

R. H. Hardin, Mar 21 2012

Status

approved