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A278177
T(n,k)=Number of nXk 0..1 arrays with every element both equal and not equal to some elements at offset (-1,0) (-1,1) (0,-1) (0,1) (1,-1) or (1,0), with upper left element zero.
8
0, 0, 0, 0, 2, 0, 0, 5, 5, 0, 0, 13, 18, 13, 0, 0, 43, 126, 126, 43, 0, 0, 137, 737, 1476, 737, 137, 0, 0, 436, 4551, 17396, 17396, 4551, 436, 0, 0, 1394, 27692, 205363, 396024, 205363, 27692, 1394, 0, 0, 4458, 169131, 2419304, 9120939, 9120939, 2419304
OFFSET
1,5
COMMENTS
Table starts
.0.....0.......0..........0.............0................0...................0
.0.....2.......5.........13............43..............137.................436
.0.....5......18........126...........737.............4551...............27692
.0....13.....126.......1476.........17396...........205363.............2419304
.0....43.....737......17396........396024..........9120939...........209105063
.0...137....4551.....205363.......9120939........408355632.........18218081491
.0...436...27692....2419304.....209105063......18218081491.......1580935773900
.0..1394..169131...28515138....4797179760.....813097394374.....137264328312479
.0..4458.1032173..336046126..110034231906...36285966496008...11916307472109969
.0.14258.6300804.3960336818.2523955236624.1619341940295084.1034507705866421424
LINKS
FORMULA
Empirical for column k:
k=2: a(n) = 3*a(n-1) +a(n-2) -3*a(n-4) -2*a(n-5) -a(n-6) for n>7
k=3: [order 16] for n>18
k=4: [order 40] for n>41
EXAMPLE
Some solutions for n=4 k=4
..0..1..1..0. .0..0..1..1. .0..1..1..1. .0..0..0..0. .0..1..1..0
..0..1..0..0. .1..1..0..1. .0..1..0..0. .1..1..1..1. .0..0..0..1
..1..0..1..0. .0..0..0..1. .1..1..0..1. .1..0..1..1. .0..1..1..1
..0..0..1..1. .1..1..0..0. .1..0..0..1. .1..0..0..1. .0..0..0..1
CROSSREFS
Sequence in context: A223705 A358304 A285192 * A095221 A078112 A281190
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Nov 13 2016
STATUS
approved