OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..37
FORMULA
Empirical: a(n) = 5*a(n-1) - a(n-2) - 31*a(n-3) + 39*a(n-4) + 56*a(n-5) - 116*a(n-6) - 14*a(n-7) + 115*a(n-8) - 34*a(n-9) - 30*a(n-10) + 12*a(n-11).
Empirical g.f.: 2*x*(12 - 30*x - 70*x^2 + 201*x^3 + 117*x^4 - 454*x^5 - 24*x^6 + 397*x^7 - 76*x^8 - 99*x^9 + 34*x^10) / ((1 - x)*(1 - 2*x)*(1 - x - x^2)*(1 - 2*x^2)*(1 - 3*x^2)*(1 - x - 2*x^2 + x^3)). - Colin Barker, Jul 19 2018
EXAMPLE
Some solutions for n=5;
.-2...-1...-1....0...-2....0....0....2....2...-2....1...-1...-1....1....0....2
.-1....1....1....1....0....1...-2...-2...-2...-2...-1...-1...-2....1...-2...-1
..0....0...-1....0....2....0....0...-2...-2...-2....1...-1...-1...-1....2...-1
..1...-1...-1...-2....0...-1...-2....2...-2....1...-1....1....0....1....2...-1
..0....1...-1....0...-2...-2....0....2....2...-2....1...-1...-1....1....2....2
.-1...-1...-1....1....2...-1...-2....2....0....1....1....1....0...-1....2...-1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 16 2012
STATUS
approved