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A303309 Number of nX3 0..1 arrays with every element equal to 0, 1, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
3, 3, 12, 11, 19, 34, 53, 83, 136, 223, 359, 578, 937, 1519, 2456, 3971, 6427, 10402, 16829, 27227, 44056, 71287, 115343, 186626, 301969, 488599, 790568, 1279163, 2069731, 3348898, 5418629, 8767523, 14186152, 22953679, 37139831, 60093506 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A303314.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-3) +a(n-4) for n>7

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A303314.

Sequence in context: A066437 A153270 A065957 * A268774 A240801 A032308

Adjacent sequences:  A303306 A303307 A303308 * A303310 A303311 A303312

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 21 2018

STATUS

approved

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Last modified March 8 11:15 EST 2021. Contains 341948 sequences. (Running on oeis4.)