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A231310 Number of (n+1) X (1+1) 0..2 arrays with no element equal to a strict majority of its horizontal, vertical, diagonal and diagonal neighbors, with values 0..2 introduced in row major order. 1
9, 57, 414, 2942, 20996, 150012, 1071848, 7659800, 54741648, 391224688, 2796005280, 19982550880, 142811894848, 1020652809152, 7294436846208, 52132137724288, 372579805702400, 2662766563813120, 19030354564815360 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) - 2*a(n-2) - 24*a(n-3) - 40*a(n-4) + 16*a(n-5).

Empirical g.f.: x*(9 - 15*x - 24*x^2 - 40*x^3 + 16*x^4) / (1 - 8*x + 2*x^2 + 24*x^3 + 40*x^4 - 16*x^5). - Colin Barker, Sep 28 2018

EXAMPLE

Some solutions for n=3:

..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..1

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

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

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

CROSSREFS

Column 1 of A231315.

Sequence in context: A155605 A199485 A102303 * A009060 A112616 A197673

Adjacent sequences:  A231307 A231308 A231309 * A231311 A231312 A231313

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 07 2013

STATUS

approved

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Last modified June 30 03:34 EDT 2022. Contains 354913 sequences. (Running on oeis4.)