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A306136 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 4, 6 or 7 king-move adjacent elements, with upper left element zero. 7
1, 1, 1, 1, 4, 1, 1, 8, 8, 1, 1, 24, 13, 24, 1, 1, 82, 64, 64, 82, 1, 1, 272, 240, 498, 240, 272, 1, 1, 908, 842, 2922, 2922, 842, 908, 1, 1, 3076, 3302, 16877, 31843, 16877, 3302, 3076, 1, 1, 10444, 12740, 111073, 267988, 267988, 111073, 12740, 10444, 1, 1, 35480, 48468 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.1.....1.....1.......1.........1...........1............1..............1

.1.....4.....8......24........82.........272..........908...........3076

.1.....8....13......64.......240.........842.........3302..........12740

.1....24....64.....498......2922.......16877.......111073.........700859

.1....82...240....2922.....31843......267988......2889140.......29281552

.1...272...842...16877....267988.....3176303.....50158767......730698959

.1...908..3302..111073...2889140....50158767...1284005626....29447872807

.1..3076.12740..700859..29281552...730698959..29447872807..1028875496355

.1.10444.48468.4405884.289967701.10451513277.652802237683.34579655304548

LINKS

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

FORMULA

Empirical for column k:

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

k=2: a(n) = 4*a(n-1) -2*a(n-2) +2*a(n-3) -6*a(n-4) -4*a(n-5) for n>6

k=3: [order 20]

k=4: [order 71] for n>72

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 2 is A303882.

Sequence in context: A316576 A304551 A316376 * A317271 A304419 A316244

Adjacent sequences:  A306133 A306134 A306135 * A306137 A306138 A306139

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Jun 22 2018

STATUS

approved

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Last modified August 25 05:19 EDT 2019. Contains 326318 sequences. (Running on oeis4.)