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A239178
T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no element greater than all horizontal neighbors or equal to all vertical neighbors
16
6, 26, 12, 98, 82, 36, 378, 514, 676, 96, 1512, 3358, 9604, 4338, 264, 6018, 22396, 142884, 130890, 29380, 720, 23890, 148820, 2286144, 4140964, 1876940, 196698, 1968, 94846, 990458, 36216324, 141857204, 127574544, 26726740, 1321986, 5376
OFFSET
1,1
LINKS
N. H. Bong, C. Dalfó, and M. À. Fiol, and D. Závacká, Some inner metric parameters of a digraph: Iterated line digraphs and integer sequences, arXiv:2409.02125 [math.CO], 2024. See p. 19.
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1) +2*a(n-2)
k=2: [order 19]
k=3: [order 67]
Empirical for row n:
n=1: a(n) = 4*a(n-1) -a(n-2) +3*a(n-3) +3*a(n-4) -4*a(n-5) +a(n-6)
n=2: [order 31]
n=3: [order 21]
EXAMPLE
Some solutions for n=3 k=4
..0..0..0..2..2....0..1..2..2..2....2..2..1..1..0....1..1..0..1..1
..2..2..2..1..1....2..2..1..1..1....0..0..0..2..2....0..2..2..2..0
..2..2..2..0..0....2..2..2..2..2....0..0..1..2..2....0..0..0..0..0
..0..0..0..1..1....1..1..0..0..0....2..2..2..0..0....2..2..2..1..1
Table starts
....6......26.........98...........378.............1512................6018
...12......82........514..........3358............22396..............148820
...36.....676.......9604........142884..........2286144............36216324
...96....4338.....130890.......4140964........141857204..........4845741276
..264...29380....1876940.....127574544.......9704723126........733415243746
..720..196698...26726740....3901908720.....652274371446.....108383467365104
.1968.1321986..381984614..119751372066...44086966064930...16126266923705212
.5376.8867938.5442841504.3664449484670.2970697967221324.2391741572658733884
CROSSREFS
Sequence in context: A329819 A337400 A036175 * A154869 A043354 A023727
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 11 2014
STATUS
approved