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A295913 Number of n X 3 0..1 arrays with each 1 adjacent to 0 or 3 king-move neighboring 1s. 1
5, 13, 39, 115, 337, 993, 2919, 8587, 25257, 74289, 218511, 642715, 1890449, 5560465, 16355255, 48106475, 141497817, 416194129, 1224171199, 3600711835, 10590941633, 31151630513, 91627743527, 269508954923, 792719257161, 2331662118065 (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) = 2*a(n-1) + 3*a(n-2) - 2*a(n-4).

Empirical g.f.: x*(5 + 3*x - 2*x^2 - 2*x^3) / (1 - 2*x - 3*x^2 + 2*x^4). - Colin Barker, Feb 22 2019

EXAMPLE

Some solutions for n=7:

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

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

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

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

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

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

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

CROSSREFS

Column 3 of A295918.

Sequence in context: A129924 A080143 A077919 * A272225 A272585 A026069

Adjacent sequences:  A295910 A295911 A295912 * A295914 A295915 A295916

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 29 2017

STATUS

approved

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Last modified May 28 10:28 EDT 2020. Contains 334680 sequences. (Running on oeis4.)