A210384 Number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock having one, two or three distinct clockwise edge differences.

597, 13399, 300653, 6747079, 151416037, 3398046223, 76258263901, 1711372650743, 38406282159749, 861906092362239, 19342723916497469, 434085536538192695, 9741660680711022261, 218620398125347551423, 4906235193671989155869

Offset

1,1

Comments

Column 2 of A210390.

Links

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

Formula

Empirical: a(n) = 26*a(n-1) - 76*a(n-2) - 93*a(n-3) + 144*a(n-4) + 66*a(n-5) - 32*a(n-6).

Empirical g.f.: x*(597 - 2123*x - 2349*x^2 + 3946*x^3 + 1750*x^4 - 864*x^5) / (1 - 26*x + 76*x^2 + 93*x^3 - 144*x^4 - 66*x^5 + 32*x^6). - Colin Barker, Jul 15 2018

Example

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

Crossrefs

Cf. A210390.

Sequence in context: A293098 A160149 A251224 * A215195 A262252 A252265

Adjacent sequences: A210381 A210382 A210383 * A210385 A210386 A210387

Keyword

nonn

Author

R. H. Hardin, Mar 20 2012

Status

approved