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A318086 Number of nX3 0..1 arrays with every element unequal to 0, 2, 3 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
1, 2, 2, 7, 7, 11, 15, 62, 104, 141, 275, 741, 1325, 2194, 4346, 9703, 17959, 32463, 64123, 132534, 250208, 470401, 923631, 1843613, 3523413, 6742322, 13174390, 25884507, 49819771, 96089259, 187177999, 365170718, 705571836, 1365582829 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A318091.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) -a(n-2) +2*a(n-3) +4*a(n-4) -12*a(n-5) +7*a(n-6) -12*a(n-7) +20*a(n-8) -6*a(n-9) +13*a(n-10) +10*a(n-11) -19*a(n-12) -2*a(n-13) -26*a(n-14) +26*a(n-15) -4*a(n-16) +10*a(n-17) -10*a(n-18) -2*a(n-19) -a(n-20) +a(n-22) +a(n-24)

EXAMPLE

All solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A318091.

Sequence in context: A021443 A045923 A306238 * A244049 A271229 A199886

Adjacent sequences:  A318083 A318084 A318085 * A318087 A318088 A318089

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 16 2018

STATUS

approved

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Last modified February 16 21:31 EST 2020. Contains 331975 sequences. (Running on oeis4.)