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A303184 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 2, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
8, 81, 135, 297, 931, 2569, 6668, 17934, 48674, 131037, 353419, 953231, 2569308, 6928326, 18683550, 50378075, 135840557, 366289949, 987683660, 2663241442, 7181313510, 19364081749, 52214352523, 140793629575, 379643605448 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A303182.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -4*a(n-2) +4*a(n-3) -9*a(n-4) +6*a(n-5) -5*a(n-6) +4*a(n-7) -4*a(n-8) +14*a(n-9) -9*a(n-10) -2*a(n-12) +8*a(n-13) +2*a(n-14) -8*a(n-15) -4*a(n-16) +4*a(n-17) for n>22

EXAMPLE

Some solutions for n=5

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

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

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

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

CROSSREFS

Cf. A303182.

Sequence in context: A301939 A302417 A227227 * A302325 A303018 A247536

Adjacent sequences:  A303181 A303182 A303183 * A303185 A303186 A303187

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 19 2018

STATUS

approved

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Last modified December 1 11:36 EST 2021. Contains 349429 sequences. (Running on oeis4.)