OFFSET
1,4
COMMENTS
Column 1 of A198654.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..200
FORMULA
Empirical: a(n) = 6*a(n-1) +a(n-2) -60*a(n-3) +50*a(n-4) +226*a(n-5) -231*a(n-6) -416*a(n-7) +361*a(n-8) +388*a(n-9) -180*a(n-10) -144*a(n-11) for n>12.
Empirical g.f.: x^2*(1 - 5*x - 5*x^2 + 50*x^3 - 4*x^4 - 184*x^5 + 36*x^6 + 303*x^7 - 3*x^8 - 189*x^9 - 53*x^10) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)*(1 - 3*x)*(1 - x - x^2)*(1 - x - 3*x^2)*(1 - x - 4*x^2)). - Colin Barker, May 15 2018
EXAMPLE
All solutions for n=5:
..0....0....0
..0....0....0
..0....0....1
..1....0....1
..1....0....1
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 28 2011
STATUS
approved