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A239849
T(n,k)=Number of nXk 0..3 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of the elements above it or two plus the sum of the elements diagonally to its northwest, modulo 4
7
2, 3, 3, 4, 8, 4, 5, 17, 17, 5, 6, 35, 68, 35, 6, 7, 64, 244, 244, 64, 7, 8, 109, 777, 1613, 777, 109, 8, 9, 176, 2221, 9066, 9066, 2221, 176, 9, 10, 272, 5853, 46260, 94613, 46260, 5853, 272, 10, 11, 405, 14488, 214126, 874352, 874352, 214126, 14488, 405, 11, 12
OFFSET
1,1
COMMENTS
Table starts
..2...3.....4........5..........6...........7............8............9
..3...8....17.......35.........64.........109..........176..........272
..4..17....68......244........777........2221.........5853........14488
..5..35...244.....1613.......9066.......46260.......214126.......921674
..6..64...777.....9066......94613......874352......7359682.....57010666
..7.109..2221....46260.....874352....15039319....232886648...3315673203
..8.176..5853...214126....7359682...232886648...6712505927.177152281120
..9.272.14488...921674...57010666..3315673203.177152281120
.10.405.34057..3745690..415293446.44101959522
.11.584.76495.14493362.2875073417
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = n + 1
k=2: a(n) = (1/24)*n^4 + (1/12)*n^3 + (11/24)*n^2 + (53/12)*n - 6 for n>2
k=3: [polynomial of degree 13] for n>9
k=4: [polynomial of degree 40] for n>31
k=5: [polynomial of degree 121] for n>98
EXAMPLE
Some solutions for n=4 k=4
..0..0..0..0....0..0..0..3....3..3..0..0....0..0..0..0....0..0..3..3
..0..0..0..3....3..3..0..1....3..2..3..3....0..3..3..0....0..3..3..2
..0..0..3..1....3..2..3..0....0..0..2..1....0..3..2..0....3..1..2..0
..0..0..3..2....0..3..1..3....0..3..3..0....0..0..3..2....3..2..0..1
CROSSREFS
Sequence in context: A238812 A227269 A156353 * A202560 A227165 A173933
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Mar 28 2014
STATUS
approved