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A278280 T(n,k)=Number of nXk 0..1 arrays with every element both equal and not equal to some elements at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero. 14
0, 0, 0, 0, 2, 0, 0, 4, 5, 0, 0, 13, 25, 16, 0, 0, 36, 122, 136, 49, 0, 0, 109, 661, 1461, 839, 153, 0, 0, 317, 3723, 15728, 16842, 5013, 476, 0, 0, 938, 20736, 172091, 350649, 196726, 30370, 1483, 0, 0, 2754, 115446, 1870365, 7466627, 7974561, 2293193 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Table starts

.0.....0.......0..........0.............0................0..................0

.0.....2.......4.........13............36..............109................317

.0.....5......25........122...........661.............3723..............20736

.0....16.....136.......1461.........15728...........172091............1870365

.0....49.....839......16842........350649..........7466627..........157609938

.0...153....5013.....196726.......7974561........329985827........13538466880

.0...476...30370....2293193.....180592726......14526103064......1158266740087

.0..1483..183403...26748095....4093629985.....640011857446.....99182079495633

.0..4619.1108525..311952675...92770708201...28192246592564...8491049196878995

.0.14388.6699034.3638315600.2102508396678.1241921389868057.726961954823301592

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..287

FORMULA

Empirical for column k:

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

k=3: a(n) = 6*a(n-1) +3*a(n-2) -17*a(n-3) +19*a(n-5) -16*a(n-6) +8*a(n-7) for n>9

k=4: [order 17] for n>19

k=5: [order 44] for n>46

k=6: [order 98] for n>101

Empirical for row n:

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

n=3: [order 16]

n=4: [order 40]

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Sequence in context: A115179 A131742 A257813 * A213370 A244138 A284611

Adjacent sequences:  A278277 A278278 A278279 * A278281 A278282 A278283

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 16 2016

STATUS

approved

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Last modified November 16 02:33 EST 2018. Contains 317252 sequences. (Running on oeis4.)