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A305637 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2, 4, 5 or 6 king-move adjacent elements, with upper left element zero. 1
4, 14, 29, 78, 255, 743, 2197, 6663, 20052, 60193, 181342, 546463, 1645639, 4957325, 14936474, 45001409, 135584151, 408514453, 1230861778, 3708615800, 11174194280, 33668360081, 101444455039, 305657427545, 920962321425, 2774910487762 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A305642.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +3*a(n-2) +9*a(n-3) -11*a(n-4) -37*a(n-5) -56*a(n-6) +14*a(n-7) +135*a(n-8) +177*a(n-9) +40*a(n-10) -179*a(n-11) -188*a(n-12) -61*a(n-13) +34*a(n-14) +3*a(n-15) for n>17

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305642.

Sequence in context: A338311 A244714 A218212 * A103779 A049451 A079776

Adjacent sequences:  A305634 A305635 A305636 * A305638 A305639 A305640

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 07 2018

STATUS

approved

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Last modified December 9 09:37 EST 2021. Contains 349627 sequences. (Running on oeis4.)