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A318209 Number of nX3 0..1 arrays with every element unequal to 1, 2, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
1, 6, 4, 21, 47, 125, 329, 842, 2254, 5893, 15435, 40669, 106859, 280658, 738110, 1940361, 5099669, 13407853, 35248057, 92658886, 243597948, 640404049, 1683558645, 4425986909, 11635671179, 30589415206, 80417882852, 211414206553 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A318214.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +5*a(n-2) +6*a(n-3) -8*a(n-4) -32*a(n-5) -19*a(n-6) +17*a(n-7) +43*a(n-8) +36*a(n-9) +24*a(n-10) +8*a(n-11) -10*a(n-12) -66*a(n-13) -26*a(n-14) +28*a(n-15) +8*a(n-16) -20*a(n-17) -2*a(n-18) +46*a(n-19) -18*a(n-20) -44*a(n-21) +32*a(n-23) -5*a(n-24) -15*a(n-25) +13*a(n-26) +6*a(n-27) -8*a(n-28) -4*a(n-29) +5*a(n-30) +a(n-31) -a(n-32) for n>33

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A318214.

Sequence in context: A321417 A185734 A292696 * A120462 A236602 A169689

Adjacent sequences:  A318206 A318207 A318208 * A318210 A318211 A318212

KEYWORD

nonn

AUTHOR

R. H. Hardin, Aug 21 2018

STATUS

approved

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Last modified January 21 11:59 EST 2019. Contains 319355 sequences. (Running on oeis4.)