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A297728 Number of nX3 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 or 4 neighboring 1s. 1
1, 8, 17, 39, 151, 385, 1026, 3272, 8945, 24901, 74075, 208094, 588488, 1706080, 4842007, 13774525, 39552499, 112678747, 321268652, 919208426, 2622325086, 7483126614, 21382095851, 61030208100, 174213589553, 497546313443 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A297733.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +13*a(n-3) -2*a(n-4) +4*a(n-5) -11*a(n-6) -3*a(n-7) -a(n-8)

EXAMPLE

Some solutions for n=7

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

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

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

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

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

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

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

CROSSREFS

Cf. A297733.

Sequence in context: A209376 A159696 A049713 * A188129 A041849 A041124

Adjacent sequences:  A297725 A297726 A297727 * A297729 A297730 A297731

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 04 2018

STATUS

approved

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Last modified July 21 06:55 EDT 2019. Contains 325192 sequences. (Running on oeis4.)