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A208081 Number of 6 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 0 1 0 vertically. 1
25, 625, 7225, 99225, 1288225, 17098225, 224850025, 2968615225, 39126818025, 516077008225, 6804820046025, 89738392111225, 1183352776011025, 15604910211748225, 205780172363700025, 2713612593438576025 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 6 of A208078.

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) +59*a(n-2) -216*a(n-3) -146*a(n-4) +568*a(n-5) -58*a(n-6) -208*a(n-7) +35*a(n-8) +6*a(n-9) -a(n-10).

Empirical g.f.: 25*x*(1 + 15*x - 20*x^2 - 180*x^3 + 334*x^4 - 26*x^5 - 144*x^6 + 32*x^7 + 5*x^8 - x^9) / ((1 - 16*x + 38*x^2 - 12*x^3 + x^4)*(1 + 6*x - x^2 - 16*x^3 - x^4 + 6*x^5 + x^6)). - Colin Barker, Jan 20 2018

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

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

CROSSREFS

Sequence in context: A207424 A207739 A288854 * A207209 A207203 A206858

Adjacent sequences:  A208078 A208079 A208080 * A208082 A208083 A208084

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 23 2012

STATUS

approved

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Last modified October 20 05:54 EDT 2021. Contains 348099 sequences. (Running on oeis4.)