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A263602
T(n,k)=Number of (n+1)X(k+1) arrays of permutations of 0..(n+1)*(k+1)-1 filled by rows with each element moved a city block distance of 0 or 2, and rows and columns in increasing lexicographic order.
9
2, 7, 8, 15, 144, 24, 27, 1687, 1962, 60, 55, 13455, 69792, 24091, 160, 109, 105222, 1880912, 2736666, 317857, 448, 199, 747253, 51961032, 248766606, 123176874, 4177099, 1232, 347, 4989566, 1372902790, 25103852988, 40226420700, 5641347668
OFFSET
1,1
COMMENTS
Table starts
....2.........7...........15............27.............55...........109
....8.......144.........1687.........13455.........105222........747253
...24......1962........69792.......1880912.......51961032....1372902790
...60.....24091......2736666.....248766606....25103852988.2343241421547
..160....317857....123176874...40226420700.14573046651208
..448...4177099...5641347668.6430889476830
.1232..54493144.249947653938
.3344.712019936
.9120
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 2*a(n-1) +4*a(n-3) +4*a(n-4)
k=2: [order 53]
Empirical for row n:
n=1: a(n) = 3*a(n-1) -3*a(n-2) +2*a(n-3) -a(n-4) -a(n-5) +a(n-6) for n>8
n=2: [order 73] for n>77
EXAMPLE
Some solutions for n=3 k=4
..0..1..2..3..4....0..1..2..7.14....0..1..2..3.14....0..1..2..3..4
..5..6.11.18..9....5.12.13.18..3....5.12.11..6..9....5.12.17..6..9
.10..7.16.19..8...10.17..6.19..4...10..7.16.19..4...10.13.18..7..8
.15.12.13.14.17...15.16.11..8..9...15.18.17..8.13...15.16.11.14.19
CROSSREFS
Sequence in context: A023178 A334227 A080572 * A162664 A341706 A032689
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Oct 22 2015
STATUS
approved