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A188821 Number of n X 6 binary arrays without the pattern 0 1 diagonally or antidiagonally. 1
64, 441, 1296, 2704, 4624, 7056, 10000, 13456, 17424, 21904, 26896, 32400, 38416, 44944, 51984, 59536, 67600, 76176, 85264, 94864, 104976, 115600, 126736, 138384, 150544, 163216, 176400, 190096, 204304, 219024, 234256, 250000, 266256, 283024 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A188824.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 256*n^2 - 384*n + 144 for n>2.

Conjectures from Colin Barker, Apr 30 2018: (Start)

G.f.: x*(64 + 249*x + 165*x^2 + 75*x^3 - 41*x^4) / (1 - x)^3.

a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>5.

(End)

EXAMPLE

Some solutions for 3 X 6:

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

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

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

CROSSREFS

Cf. A188824.

Sequence in context: A188785 A317237 A282771 * A181210 A092211 A130812

Adjacent sequences:  A188818 A188819 A188820 * A188822 A188823 A188824

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 11 2011

STATUS

approved

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Last modified July 31 06:15 EDT 2021. Contains 346369 sequences. (Running on oeis4.)