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A240046
T(n,k)=Number of nXk 0..3 arrays with no element equal to zero plus the sum of elements to its left or zero plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4
12
2, 2, 2, 4, 4, 4, 6, 9, 10, 6, 8, 20, 26, 22, 8, 14, 33, 72, 93, 50, 14, 20, 76, 174, 346, 309, 119, 20, 30, 117, 597, 1110, 1496, 1043, 276, 30, 48, 232, 1187, 5780, 7514, 8567, 3597, 637, 48, 70, 398, 3115, 17297, 55034, 61858, 46381, 12865, 1473, 70, 108, 675, 7269
OFFSET
1,1
COMMENTS
Table starts
..2....2......4.......6.........8..........14..........20..........30
..2....4......9......20........33..........76.........117.........232
..4...10.....26......72.......174.........597........1187........3115
..6...22.....93.....346......1110........5780.......17297.......57800
..8...50....309....1496......7514.......55034......236282.....1248277
.14..119...1043....8567.....61858......640643.....4593632....35084947
.20..276...3597...46381....515675.....8300260...104619164..1204711882
.30..637..12865..268672...4743056...119956268..2789729009.49892724623
.48.1473..45491.1556758..45158204..1944727891.80805084589
.70.3355.163686.9438166.453408919.34311716212
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-2) +2*a(n-3)
k=2: [order 38] for n>40
Empirical for row n:
n=1: a(n) = a(n-2) +2*a(n-3)
n=2: [order 18] for n>22
n=3: [order 76] for n>96
EXAMPLE
Some solutions for n=3 k=4
..2..3..2..2....3..2..2..2....2..3..3..3....2..3..2..2....2..3..3..3
..3..1..1..0....2..0..0..0....3..1..2..0....3..1..1..3....3..1..1..2
..3..1..2..3....2..0..0..0....2..1..2..0....2..1..1..2....3..2..2..2
CROSSREFS
Row and Column 1 are A239851
Sequence in context: A007294 A053282 A218084 * A363947 A001584 A180019
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 31 2014
STATUS
approved