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A231397 Number of (1+1) X (n+1) 0..2 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order. 1
3, 7, 14, 33, 78, 189, 482, 1225, 3238, 8565, 23114, 62657, 171342, 470573, 1297330, 3586745, 9934454, 27559269, 76525210, 212662577, 591289630, 1644693789, 4576035586, 12734509097, 35443628358, 98659578197, 274645954794 (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) = 4*a(n-1) + a(n-2) - 16*a(n-3) + 4*a(n-4) + 24*a(n-5) - 16*a(n-6).

Empirical g.f.: x*(3 - 5*x - 17*x^2 + 18*x^3 + 32*x^4 - 32*x^5) / ((1 - x)*(1 - 2*x)*(1 - x - 6*x^2 + 8*x^4)). - Colin Barker, Sep 28 2018

EXAMPLE

Some solutions for n=5:

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

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

CROSSREFS

Row 1 of A231396.

Sequence in context: A223136 A089526 A261051 * A231464 A146920 A079939

Adjacent sequences:  A231394 A231395 A231396 * A231398 A231399 A231400

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 08 2013

STATUS

approved

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Last modified May 17 19:39 EDT 2021. Contains 343988 sequences. (Running on oeis4.)