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A274065
T(n,k)=Number of nXk 0..2 arrays with no three equal values forming an isosceles right triangle, and new values introduced in 0..2 order.
2
1, 2, 2, 5, 9, 5, 14, 50, 50, 14, 41, 285, 264, 285, 41, 122, 1617, 435, 435, 1617, 122, 365, 9188, 546, 8, 546, 9188, 365, 1094, 52193, 1209, 1, 1, 1209, 52193, 1094, 3281, 296511, 3272, 0, 0, 0, 3272, 296511, 3281, 9842, 1684466, 8412, 0, 0, 0, 0, 8412, 1684466, 9842
OFFSET
1,2
COMMENTS
Table starts
.....1.......2.....5..14...41..122...365...1094....3281....9842.29525
.....2.......9....50.285.1617.9188.52193.296511.1684466.9569425
.....5......50...264.435..546.1209..3272...8412...20634
....14.....285...435...8....1....0.....0......0
....41....1617...546...1....0....0.....0
...122....9188..1209...0....0....0
...365...52193..3272...0....0
..1094..296511..8412...0
..3281.1684466.20634
..9842.9569425
.29525
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 4*a(n-1) -3*a(n-2)
k=2: a(n) = 6*a(n-1) -11*a(n-3) +4*a(n-4) for n>5
k=3: [order 40] for n>49
EXAMPLE
Some solutions for n=4 k=4
..0..1..0..2. .0..1..2..1. .0..0..0..1. .0..1..1..2. .0..0..1..1
..2..2..2..0. .1..0..0..0. .2..2..2..1. .1..0..2..1. .2..1..0..2
..1..1..1..0. .1..2..2..2. .1..1..1..2. .2..0..2..0. .2..1..0..2
..0..2..0..1. .2..1..0..1. .0..0..0..2. .1..0..2..1. .2..1..0..2
CROSSREFS
Column 1 is A007051(n-1).
Column 2 is A231413(n-1).
Sequence in context: A275401 A011273 A274068 * A233073 A275266 A223387
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Jun 09 2016
STATUS
approved