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A204487 Number of (n+2)X5 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly one way, and new values 0..1 introduced in row major order 1
610, 1189, 2547, 5407, 11331, 23851, 50897, 109489, 236402, 512911, 1118772, 2440948, 5333293, 11686972, 25595013, 56075719, 123070849, 269926981, 592042603, 1300024973, 2853037552, 6260804838, 13749466588, 30182600469 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A204492

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +9*a(n-3) -5*a(n-4) -10*a(n-5) -7*a(n-6) -20*a(n-7) +20*a(n-8) -15*a(n-9) +48*a(n-10) -10*a(n-11) +20*a(n-12) -21*a(n-13) -5*a(n-14) -6*a(n-15) -3*a(n-16) +4*a(n-17) for n>25

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A263393 A137563 A301561 * A090177 A120719 A045730

Adjacent sequences:  A204484 A204485 A204486 * A204488 A204489 A204490

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 15 2012

STATUS

approved

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Last modified December 8 20:37 EST 2021. Contains 349596 sequences. (Running on oeis4.)