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A302724 Number of nX3 0..1 arrays with every element equal to 1, 2, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
1, 7, 22, 83, 301, 1079, 4064, 15183, 55012, 207349, 770421, 2830250, 10617371, 39400644, 145704104, 544623685, 2020998479, 7497256552, 27957348859, 103787074017, 385563034716, 1435728019366, 5332352333196, 19821039046245 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A302728.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +5*a(n-2) +27*a(n-3) -64*a(n-4) -67*a(n-5) +25*a(n-6) -22*a(n-7) -66*a(n-8) -240*a(n-9) +232*a(n-10) +168*a(n-11) -16*a(n-12) +64*a(n-13) +64*a(n-14) +256*a(n-15) -256*a(n-16)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A302728.

Sequence in context: A282035 A302273 A151822 * A305083 A231214 A041913

Adjacent sequences:  A302721 A302722 A302723 * A302725 A302726 A302727

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 12 2018

STATUS

approved

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Last modified January 29 14:07 EST 2020. Contains 331338 sequences. (Running on oeis4.)