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A281202 Number of n X 5 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
5, 52, 176, 470, 1141, 2602, 5712, 12208, 25577, 52784, 107636, 217370, 435473, 866550, 1714460, 3375236, 6616061, 12919308, 25142632, 48783294, 94395997, 182209890, 350933080, 674521464, 1294078657, 2478473672, 4739410828 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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-4) + 4*a(n-5) - a(n-8).

Empirical g.f.: x*(5 + 32*x - 12*x^2 - 26*x^3 - 25*x^4 + 2*x^5 + 12*x^6 + 4*x^7) / ((1 - x)^2*(1 - x - x^2 - x^3)^2). - Colin Barker, Feb 17 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 5 of A281205.

Sequence in context: A247713 A067282 A045539 * A173719 A081075 A247766

Adjacent sequences:  A281199 A281200 A281201 * A281203 A281204 A281205

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 17 2017

STATUS

approved

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Last modified March 20 15:43 EDT 2019. Contains 321345 sequences. (Running on oeis4.)