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A297333 Number of n X 3 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0 or 2 neighboring 1s. 1
5, 22, 96, 421, 1847, 8105, 35568, 156089, 684994, 3006088, 13192185, 57893767, 254066201, 1114966916, 4893020877, 21472971950, 94233917248, 413544579709, 1814836148199, 7964389829833, 34951643113640, 153384927463937 (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) = 5*a(n-1) - 2*a(n-2) - 3*a(n-3).

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

EXAMPLE

Some solutions for n=5:

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

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

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

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

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

CROSSREFS

Column 3 of A297338.

Sequence in context: A266430 A083586 A200676 * A129158 A129164 A123347

Adjacent sequences:  A297330 A297331 A297332 * A297334 A297335 A297336

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 28 2017

STATUS

approved

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Last modified December 1 22:24 EST 2020. Contains 338858 sequences. (Running on oeis4.)