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A305530 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 1, 2, 3, 4 or 6 king-move adjacent elements, with upper left element zero. 7
1, 2, 2, 4, 8, 4, 8, 30, 30, 8, 16, 112, 161, 112, 16, 32, 420, 880, 880, 420, 32, 64, 1576, 4779, 7385, 4779, 1576, 64, 128, 5912, 26000, 61139, 61139, 26000, 5912, 128, 256, 22176, 141474, 506359, 767417, 506359, 141474, 22176, 256, 512, 83184, 769617 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Table starts

...1.....2.......4.........8..........16............32.............64

...2.....8......30.......112.........420..........1576...........5912

...4....30.....161.......880........4779.........26000.........141474

...8...112.....880......7385.......61139........506359........4205030

..16...420....4779.....61139......767417.......9599897......120736482

..32..1576...26000....506359.....9599897.....180860170.....3433486971

..64..5912..141474...4205030...120736482....3433486971....98651246976

.128.22176..769617..34889423..1516911265...65111777047..2831187189412

.256.83184.4187055.289444806.19047231319.1233566348589.81130991759635

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..180

FORMULA

Empirical for column k:

k=1: a(n) = 2*a(n-1)

k=2: a(n) = 4*a(n-1) -2*a(n-2) +4*a(n-3)

k=3: [order 11]

k=4: [order 38] for n>39

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 1 is A000079(n-1).

Column 2 is A281949.

Sequence in context: A316183 A305769 A317118 * A317004 A316822 A317572

Adjacent sequences:  A305527 A305528 A305529 * A305531 A305532 A305533

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Jun 04 2018

STATUS

approved

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Last modified October 16 05:41 EDT 2021. Contains 348035 sequences. (Running on oeis4.)