login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A263424
T(n,k)=Number of nXk arrays of permutations of 0..n*k-1 with each element moved a city block distance of 0 or 2.
5
1, 1, 1, 2, 4, 2, 4, 36, 36, 4, 6, 196, 1272, 196, 6, 9, 961, 26244, 26244, 961, 9, 15, 5329, 532620, 1993744, 532620, 5329, 15, 25, 29584, 11751184, 141086884, 141086884, 11751184, 29584, 25, 40, 160000, 256052940, 10808097444, 34502512032
OFFSET
1,4
COMMENTS
Table starts
..1......1..........2............4.............6.............9...............15
..1......4.........36..........196...........961..........5329............29584
..2.....36.......1272........26244........532620......11751184........256052940
..4....196......26244......1993744.....141086884...10808097444.....831331827076
..6....961.....532620....141086884...34502512032.9414955824400.2581177525941432
..9...5329...11751184..10808097444.9414955824400
.15..29584..256052940.831331827076
.25.160000.5521233025
.40.868624
.64
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = a(n-1) +a(n-3) +a(n-4)
k=2: [order 15]
k=3: [order 64]
EXAMPLE
Some solutions for n=3 k=4
..2..9..0..1....8..9..7..6....0..4..7..6....8..4..0..3....5..6.10.11
..4..7.11.10....1..5.11..2....9..2..1.10....1..5.11..7....1..0..4..7
..5..6..8..3....0..4.10..3....5.11..8..3...10..9..2..6....8..9..2..3
CROSSREFS
Column 1 is A006498.
Sequence in context: A139548 A193378 A108445 * A279527 A347184 A019294
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Oct 17 2015
STATUS
approved