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A212026
T(n,k)=Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any horizontal, diagonal or antidiagonal neighbor, and containing the value n(n+1)/2-k-1
5
0, 0, 2, 0, 2, 9, 0, 0, 25, 31, 0, 0, 34, 346, 80, 0, 0, 35, 1793, 2589, 171, 0, 0, 35, 4785, 44294, 12636, 322, 0, 0, 0, 7396, 440660, 532619, 46612, 554, 0, 0, 0, 8220, 2655126, 14245030, 4022727, 141520, 891, 0, 0, 0, 8291, 9881099, 254601542, 231475447
OFFSET
1,3
COMMENTS
Table starts
...0......0........0..........0............0............0...........0
...2......2........0..........0............0............0...........0
...9.....25.......34.........35...........35............0...........0
..31....346.....1793.......4785.........7396.........8220........8291
..80...2589....44294.....440660......2655126......9881099....23187213
.171..12636...532619...14245030....254601542...3122930515.26618503099
.322..46612..4022727..231475447...9411294829.279615006837
.554.141520.22156544.2383699176.187291345391
LINKS
EXAMPLE
Some solutions for n=4 k=4
..0........0........0........0........0........0........0........0
..1.2......1.2......1.2......1.2......1.2......1.2......1.2......1.2
..3.4.3....0.3.4....3.2.3....3.4.1....3.0.3....3.4.5....0.3.4....1.3.1
..5.6.1.7..4.5.4.5..3.4.3.5..5.0.6.0..2.4.3.5..0.2.3.1..5.6.4.1..1.4.1.5
CROSSREFS
Column 1 is A211924
Sequence in context: A278748 A342286 A211930 * A246003 A242052 A344765
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Apr 26 2012
STATUS
approved