OFFSET
1,1
COMMENTS
Column 3 of A230949
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 11*a(n-1) -23*a(n-2) +150*a(n-3) +309*a(n-4) -2148*a(n-5) +10102*a(n-6) -47494*a(n-7) -27771*a(n-8) -127963*a(n-9) -856209*a(n-10) -751900*a(n-11) +518927*a(n-12) +1522290*a(n-13) +5226896*a(n-14) +6396332*a(n-15) -6910959*a(n-16) -15629371*a(n-17) +577087*a(n-18) +12661958*a(n-19) +107867*a(n-20) -3633560*a(n-21) +898870*a(n-22) +447610*a(n-23) -220949*a(n-24) -31637*a(n-25) -855*a(n-26) +2592*a(n-27) +865*a(n-28) +42*a(n-29) +4*a(n-30)
EXAMPLE
Some solutions for n=2
..0..x..0..x..1..x....0..x..2..x..2..x....0..x..0..x..3..x....0..x..2..x..2..x
..x..1..x..1..x..2....x..1..x..3..x..1....x..1..x..0..x..2....x..1..x..3..x..1
..0..x..2..x..3..x....2..x..0..x..1..x....2..x..0..x..1..x....0..x..0..x..2..x
..x..3..x..2..x..0....x..3..x..0..x..2....x..3..x..3..x..0....x..1..x..3..x..1
..2..x..1..x..1..x....2..x..2..x..3..x....2..x..2..x..2..x....0..x..2..x..0..x
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 01 2013
STATUS
approved