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A303795 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2 or 4 king-move adjacent elements, with upper left element zero. 1
4, 12, 17, 30, 70, 121, 221, 421, 800, 1511, 2832, 5340, 10089, 19009, 35825, 67558, 127375, 240150, 452774, 853653, 1609501, 3034561, 5721352, 10787091, 20338064, 38345504, 72296881, 136309037, 256998009, 484545858, 913566127, 1722443986 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A303800.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +a(n-2) +2*a(n-3) -a(n-5) -2*a(n-6) -2*a(n-7) for n>10

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A303800.

Sequence in context: A301001 A047958 A300747 * A175704 A350602 A111371

Adjacent sequences:  A303792 A303793 A303794 * A303796 A303797 A303798

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 30 2018

STATUS

approved

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Last modified May 19 17:07 EDT 2022. Contains 353847 sequences. (Running on oeis4.)