OFFSET
1,5
COMMENTS
Table starts
.1...1.....1........1...........1..............1..................1
.1...2.....3........6..........10.............20.................35
.1...3....10.......30.........140............420...............2310
.1...6....30......280........2100..........23100.............210210
.1..10...140.....2100.......60060........1051050...........42882840
.1..20...420....23100.....1051050.......85765680.........5703417720
.1..35..2310...210210....42882840.....5703417720......2061378118800
.1..70..6930..2522520...814773960...577185873264....337653735859440
.1.126.42042.25729704.41227562376.48236247979920.173457547735792320
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..1000
FORMULA
EXAMPLE
Some solutions for n=5 k=4
..1..x..2..x....0..x..6..x....1..x..6..x....1..x..4..x....0..x..6..x
..x..0..x..4....x..3..x..4....x..0..x..3....x..0..x..3....x..1..x..2
..3..x..8..x....1..x..7..x....4..x..7..x....2..x..7..x....4..x..7..x
..x..6..x..7....x..5..x..8....x..2..x..8....x..5..x..6....x..3..x..9
..5..x..9..x....2..x..9..x....5..x..9..x....8..x..9..x....5..x..8..x
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Aug 07 2012
STATUS
approved