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A302260 Number of nX3 0..1 arrays with every element equal to 0, 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
4, 29, 153, 818, 4386, 23516, 126162, 676988, 3632880, 19495940, 104627364, 561499304, 3013389264, 16171937024, 86789899608, 465775377536, 2499677308656, 13415022525008, 71994427701360, 386372643782240, 2073546883713888 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A302265.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) -2*a(n-2) +2*a(n-3) -54*a(n-4) +16*a(n-5) for n>6

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A302265.

Sequence in context: A295526 A272373 A273247 * A302960 A273300 A300467

Adjacent sequences:  A302257 A302258 A302259 * A302261 A302262 A302263

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 04 2018

STATUS

approved

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Last modified December 8 17:01 EST 2021. Contains 349596 sequences. (Running on oeis4.)