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A204378 Number of (n+2) X 7 0..1 arrays with every 3 X 3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly three ways, and new values 0..1 introduced in row major order. 1
182, 88, 98, 111, 136, 176, 241, 348, 518, 795, 1244, 1968, 3141, 5040, 8110, 13079, 21120, 34128, 55177, 89236, 144342, 233507, 377780, 611216, 988925, 1600072, 2588926, 4188927, 6777784, 10966640, 17744353, 28710924, 46455206, 75166059 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A204381.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +a(n-3) -a(n-4) -a(n-5) for n>8.

Empirical g.f.: x*(182 - 94*x - 172*x^2 - 257*x^3 + 21*x^4 + 101*x^5 + 4*x^6 + 4*x^7) / ((1 - x)*(1 - x - x^2)*(1 + x + x^2)). - Colin Barker, Jun 07 2018

EXAMPLE

Some solutions for n=3:

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

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

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

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

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

CROSSREFS

Cf. A204381.

Sequence in context: A185824 A324271 A265997 * A054572 A054985 A124185

Adjacent sequences:  A204375 A204376 A204377 * A204379 A204380 A204381

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 14 2012

STATUS

approved

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Last modified September 22 04:49 EDT 2021. Contains 347605 sequences. (Running on oeis4.)