A186591 - OEIS

A186591

Number of (n+3)X4 0..3 arrays with every 4X4 subblock commuting with each horizontal and vertical neighbor 4X4 subblock

4294967296, 48243, 430183, 3306753, 21993587, 53301263, 71095231, 78728809, 86748644, 89692007, 94541176, 120087461, 205742497, 372822912, 600755929, 913680450, 1430990335, 2201398558, 3168904216, 4468022885, 6637262756

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Column 1 of A186599

LINKS

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

FORMULA

Empirical: a(n)=2*a(n-1)-a(n-2)+3*a(n-4)-6*a(n-5)+3*a(n-6)+3*a(n-8)-3*a(n-9) for n>30

EXAMPLE

Some solutions for 5X4

..3..3..2..1....0..1..2..2....2..1..1..2....0..3..2..0....1..1..2..0

..0..3..3..1....0..0..1..0....0..2..3..3....0..3..2..0....1..1..2..0

..0..0..3..2....0..0..0..3....0..0..0..0....0..3..2..0....1..1..2..0

..0..0..0..0....0..0..0..0....0..0..0..0....0..3..2..0....1..1..2..0

..0..0..0..0....0..0..0..0....0..0..0..0....0..1..2..2....3..0..1..0

CROSSREFS

Sequence in context: A255344 A186590 A186599 * A281576 A288282 A210014

Adjacent sequences: A186588 A186589 A186590 * A186592 A186593 A186594

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 24 2011

STATUS

approved