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A204376 Number of (n+2) X 5 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
78, 54, 61, 75, 98, 139, 205, 310, 481, 759, 1206, 1931, 3105, 5002, 8073, 13043, 21082, 34091, 55141, 89198, 144305, 233471, 377742, 611179, 988889, 1600034, 2588889, 4188891, 6777746, 10966603, 17744317, 28710886, 46455169, 75166023, 121621158 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 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*(78 - 24*x - 71*x^2 - 118*x^3 - 14*x^4 + 37*x^5 + 8*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..1..0..0....0..1..1..0..0....0..1..1..0..1....0..1..1..0..0

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

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

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

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

CROSSREFS

Cf. A204381.

Sequence in context: A098024 A117330 A033398 * A176094 A124289 A181467

Adjacent sequences:  A204373 A204374 A204375 * A204377 A204378 A204379

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 14 2012

STATUS

approved

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Last modified September 25 15:27 EDT 2021. Contains 347658 sequences. (Running on oeis4.)