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A238726
T(n,k)=Number of nXk 0..2 arrays with no element equal to the sum modulo 3 of elements to its left or elements above it
8
2, 2, 2, 4, 4, 4, 4, 10, 10, 4, 8, 16, 40, 16, 8, 8, 42, 86, 86, 42, 8, 16, 64, 336, 284, 336, 64, 16, 16, 170, 704, 1506, 1506, 704, 170, 16, 32, 256, 2704, 4636, 11440, 4636, 2704, 256, 32, 32, 682, 5660, 24298, 48538, 48538, 24298, 5660, 682, 32, 64, 1024, 21504, 73300
OFFSET
1,1
COMMENTS
Table starts
..2....2.....4.......4........8..........8..........16...........16
..2....4....10......16.......42.........64.........170..........256
..4...10....40......86......336........704........2704.........5660
..4...16....86.....284.....1506.......4636.......24298........73300
..8...42...336....1506....11440......48538......359456......1502622
..8...64...704....4636....48538.....296384.....3022230.....17949864
.16..170..2704...24298...359456....3022230....43248968....354823094
.16..256..5660...73300..1502622...17949864...354823094...4105077596
.32..682.21504..381280.10971288..180550234..4990305568..79679547754
.32.1024.45176.1144292.45750856.1061806368.40601871406.909801061032
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-2)
k=2: a(n) = 5*a(n-2) -4*a(n-4)
k=3: a(n) = 17*a(n-2) -96*a(n-4) +210*a(n-6) -152*a(n-8)
k=4: [order 18]
k=5: [order 38]
k=6: [order 90]
EXAMPLE
Some solutions for n=5 k=4
..2..1..1..2....1..2..1..2....1..2..1..2....1..2..2..1....2..1..2..1
..1..0..2..1....2..0..0..1....2..1..2..1....2..1..1..2....1..2..1..0
..1..2..2..1....1..0..2..1....2..1..1..2....2..1..2..1....2..1..1..0
..2..1..1..2....2..1..2..0....1..2..2..0....1..2..1..2....1..0..2..2
..1..2..2..1....2..1..1..0....1..2..2..0....1..2..1..2....2..0..1..2
CROSSREFS
Sequence in context: A355911 A369207 A113402 * A240321 A054861 A187324
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 03 2014
STATUS
approved