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A281209 Number of 5 X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards. 1
0, 130, 448, 676, 1141, 1906, 3137, 5160, 8510, 14084, 23379, 38894, 64795, 108022, 180126, 300318, 500525, 833770, 1388053, 2309332, 3839550, 6379528, 10592935, 17578086, 29151695, 48317346, 80038622, 132514530, 219282785, 362687074 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) - 4*a(n-2) - 2*a(n-3) + 4*a(n-4) - a(n-6) for n>11.

Empirical g.f.: x^2*(130 - 72*x - 596*x^2 + 489*x^3 + 422*x^4 - 363*x^5 - 56*x^6 + 114*x^7 + 10*x^8 - 4*x^9) / ((1 - x)^2*(1 - x - x^2)^2). - Colin Barker, Feb 18 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Row 5 of A281205.

Sequence in context: A252082 A253044 A253037 * A253036 A187723 A278658

Adjacent sequences:  A281206 A281207 A281208 * A281210 A281211 A281212

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 17 2017

STATUS

approved

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Last modified January 20 19:53 EST 2020. Contains 331096 sequences. (Running on oeis4.)