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A305509 T(n,k)=Number of nXk 0..1 arrays with every element unequal to 2, 3, 4, 6 or 8 king-move adjacent elements, with upper left element zero. 5
0, 0, 0, 0, 3, 0, 0, 5, 5, 0, 0, 18, 4, 18, 0, 0, 61, 42, 42, 61, 0, 0, 209, 130, 346, 130, 209, 0, 0, 702, 464, 1767, 1767, 464, 702, 0, 0, 2381, 1722, 10182, 13314, 10182, 1722, 2381, 0, 0, 8069, 6378, 60352, 101912, 101912, 60352, 6378, 8069, 0, 0, 27330, 22939, 350540 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,5
COMMENTS
Table starts
.0....0.....0.......0........0..........0...........0.............0
.0....3.....5......18.......61........209.........702..........2381
.0....5.....4......42......130........464........1722..........6378
.0...18....42.....346.....1767......10182.......60352........350540
.0...61...130....1767....13314.....101912......855017.......6971744
.0..209...464...10182...101912....1126154....13419832.....155294889
.0..702..1722...60352...855017...13419832...235231504....3907075261
.0.2381..6378..350540..6971744..155294889..3907075261...93092873891
.0.8069.22939.2034140.56056227.1779735908.64554148567.2198342635112
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 3*a(n-1) +a(n-2) +2*a(n-3) -2*a(n-4) -4*a(n-5) for n>6
k=3: [order 18] for n>19
k=4: [order 66] for n>67
EXAMPLE
Some solutions for n=5 k=4
..0..1..1..0. .0..1..0..1. .0..1..0..1. .0..1..1..0. .0..1..1..0
..1..0..0..1. .1..1..0..1. .1..0..1..0. .0..1..1..0. .1..0..1..1
..1..0..0..1. .0..0..0..0. .1..0..0..0. .0..0..1..1. .0..1..1..0
..1..0..0..1. .1..1..0..1. .0..0..1..0. .1..0..0..1. .1..1..1..0
..0..1..1..0. .0..0..1..0. .1..1..0..1. .1..0..0..1. .0..0..0..1
CROSSREFS
Column 2 is A303684.
Column 3 is A304151.
Column 4 is A304152.
Sequence in context: A135090 A303690 A304156 * A305175 A316763 A304065
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jun 03 2018
STATUS
approved

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Last modified July 21 12:49 EDT 2024. Contains 374474 sequences. (Running on oeis4.)