OFFSET
1,1
COMMENTS
Column 5 of A230935
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 63*a(n-2) -257*a(n-4) -6639*a(n-6) +14476*a(n-8) +210885*a(n-10) +297473*a(n-12) -149746*a(n-14) +3509820*a(n-16) +15998822*a(n-18) +18439507*a(n-20) -5600207*a(n-22) -23359537*a(n-24) -11139145*a(n-26) +4160133*a(n-28) +3040715*a(n-30) -1579065*a(n-32) -872680*a(n-34) +360423*a(n-36) +62740*a(n-38) -14788*a(n-40) +16*a(n-42) -256*a(n-44)
EXAMPLE
Some solutions for n=4
..x..0..x..2..x..2..x....x..0..x..0..x..0..x....x..0..x..2..x..0..x
..1..x..3..x..1..x..3....1..x..1..x..1..x..1....1..x..3..x..1..x..3
..x..2..x..0..x..0..x....x..2..x..2..x..2..x....x..2..x..0..x..0..x
..1..x..1..x..1..x..3....1..x..3..x..1..x..3....1..x..3..x..3..x..1
..x..0..x..2..x..0..x....x..0..x..2..x..0..x....x..2..x..2..x..2..x
..3..x..1..x..3..x..3....3..x..3..x..1..x..3....1..x..1..x..1..x..1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 01 2013
STATUS
approved