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A305447 Number of nX3 0..1 arrays with every element unequal to 1, 2, 4, 5 or 8 king-move adjacent elements, with upper left element zero. 1
1, 11, 7, 20, 44, 77, 181, 379, 849, 1799, 4154, 9242, 20384, 46987, 105477, 238364, 544013, 1234035, 2805803, 6392808, 14558529, 33157368, 75581441, 172296118, 392727236, 895513084, 2042029380, 4656342833, 10619040244, 24217647660 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A305452.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +3*a(n-2) +7*a(n-3) -6*a(n-4) -18*a(n-5) -26*a(n-6) +8*a(n-7) +27*a(n-8) +47*a(n-9) +16*a(n-10) -5*a(n-11) -3*a(n-12) -7*a(n-13) -20*a(n-14) -24*a(n-15) -5*a(n-16) -6*a(n-17) for n>18

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A305452.

Sequence in context: A187866 A206419 A250032 * A060954 A038321 A298438

Adjacent sequences:  A305444 A305445 A305446 * A305448 A305449 A305450

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jun 01 2018

STATUS

approved

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Last modified May 10 04:01 EDT 2021. Contains 343748 sequences. (Running on oeis4.)