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A297334 Number of n X 4 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 0 or 2 neighboring 1s. 1
8, 53, 334, 2119, 13428, 85065, 538819, 3412881, 21617001, 136920545, 867244348, 5493058792, 34792608560, 220373681804, 1395829787253, 8841077466468, 55998698016470, 354691403972040, 2246587804789311, 14229712668714865 (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) = 8*a(n-1) - 10*a(n-2) - 4*a(n-3) + 3*a(n-4) + a(n-5).

Empirical g.f.: x*(1 - x)*(8 - 3*x - 13*x^2 - 4*x^3) / (1 - 8*x + 10*x^2 + 4*x^3 - 3*x^4 - x^5). - Colin Barker, Feb 27 2019

EXAMPLE

Some solutions for n=5:

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

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

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

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

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

CROSSREFS

Column 4 of A297338.

Sequence in context: A198846 A291662 A110099 * A091870 A252824 A054418

Adjacent sequences:  A297331 A297332 A297333 * A297335 A297336 A297337

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 28 2017

STATUS

approved

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Last modified June 16 14:36 EDT 2021. Contains 345057 sequences. (Running on oeis4.)