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A281028 Number of n X 2 0..1 arrays with no element equal to more than three of its king-move neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards. 1
0, 0, 2, 12, 58, 252, 1048, 4204, 16454, 63236, 239622, 897792, 3332864, 12277952, 44938282, 163566412, 592492026, 2137194788, 7680594760, 27511516436, 98254943022, 349979793492, 1243627373550, 4409519905928, 15603737422416 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) - 7*a(n-2) - 2*a(n-3) - 17*a(n-4) + 24*a(n-6) + 16*a(n-7) + 12*a(n-8) - 16*a(n-9) - 16*a(n-10).

Empirical g.f.: 2*x^3*(1 - 2*x^3)^2 / (1 - 3*x - x^2 - 2*x^3 + 2*x^4 + 4*x^5)^2. - Colin Barker, Feb 15 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 2 of A281034.

Sequence in context: A094780 A268594 A100103 * A054145 A285364 A282435

Adjacent sequences:  A281025 A281026 A281027 * A281029 A281030 A281031

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 13 2017

STATUS

approved

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Last modified February 19 16:24 EST 2020. Contains 332045 sequences. (Running on oeis4.)