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A304894 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 0, 2, 3, 4 or 7 king-move adjacent elements, with upper left element zero. 7
1, 1, 1, 1, 4, 1, 1, 8, 8, 1, 1, 24, 11, 24, 1, 1, 82, 40, 40, 82, 1, 1, 272, 94, 246, 94, 272, 1, 1, 908, 291, 899, 899, 291, 908, 1, 1, 3076, 776, 4262, 3145, 4262, 776, 3076, 1, 1, 10444, 2269, 18773, 17391, 17391, 18773, 2269, 10444, 1, 1, 35480, 6275, 86217 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

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

.1.....4....8.....24......82......272.......908.......3076........10444

.1.....8...11.....40......94......291.......776.......2269.........6275

.1....24...40....246.....899.....4262.....18773......86217.......393045

.1....82...94....899....3145....17391.....86300.....437461......2277571

.1...272..291...4262...17391...123297....793698....5028590.....34392736

.1...908..776..18773...86300...793698...7309444...56105221....545744025

.1..3076.2269..86217..437461..5028590..56105221..527157688...6329865862

.1.10444.6275.393045.2277571.34392736.545744025.6329865862.106200560327

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..199

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 19] for n>20

k=4: [order 49] for n>52

EXAMPLE

Some solutions for n=5 k=4

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

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

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

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

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

CROSSREFS

Column 2 is A303882.

Sequence in context: A174035 A303888 A305281 * A316576 A304551 A316376

Adjacent sequences:  A304891 A304892 A304893 * A304895 A304896 A304897

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, May 20 2018

STATUS

approved

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Last modified July 28 11:11 EDT 2021. Contains 346326 sequences. (Running on oeis4.)