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A240321
T(n,k)=Number of nXk 0..3 arrays with no element equal to two plus the sum of elements to its left or two plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4
6
2, 2, 2, 4, 4, 4, 4, 18, 18, 4, 8, 44, 172, 44, 8, 8, 184, 866, 866, 184, 8, 16, 444, 7326, 8456, 7326, 444, 16, 16, 1826, 35042, 143682, 143682, 35042, 1826, 16, 32, 4388, 291982, 1352558, 4934092, 1352558, 291982, 4388, 32, 32, 18022, 1387224, 22643786
OFFSET
1,1
COMMENTS
Table starts
..2.....2........4...........4..............8...............8...............16
..2.....4.......18..........44............184.............444.............1826
..4....18......172.........866...........7326...........35042...........291982
..4....44......866........8456.........143682.........1352558.........22643786
..8...184.....7326......143682........4934092........92600224.......3120733284
..8...444....35042.....1352558.......92600224......3462370700.....233738937688
.16..1826...291982....22643786.....3120733284....233738937688...31675283550406
.16..4388..1387224...211572262....58052954898...8672268288766.2350783897073214
.32.18022.11520638..3529400774..1946100075968.582902538705858
.32.43300.54650290.32917918872.36103692985126
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-2)
k=2: a(n) = 12*a(n-2) -24*a(n-4) +31*a(n-6) -16*a(n-8)
k=3: [order 48]
EXAMPLE
Some solutions for n=4 k=4
..3..3..1..3....1..1..3..1....3..3..3..1....3..3..1..3....3..3..1..3
..3..0..0..0....1..0..2..2....3..2..0..0....3..0..0..2....3..0..2..2
..1..0..2..0....3..0..0..2....3..0..2..2....1..0..0..0....1..0..2..2
..3..0..0..3....1..2..2..2....1..2..0..0....3..2..1..1....3..2..1..2
CROSSREFS
Column 1 is A016116(n+1)
Sequence in context: A369207 A113402 A238726 * A054861 A187324 A334207
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Apr 03 2014
STATUS
approved