OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-1) + 16*a(n-2) + 9*a(n-3) - 29*a(n-4) - 9*a(n-5) + 16*a(n-6) - a(n-7) - a(n-8).
Empirical g.f.: x*(1 - x)*(10 + 33*x + 20*x^2 - 18*x^3 - 12*x^4 + 3*x^5 + x^6) / (1 - x - 16*x^2 - 9*x^3 + 29*x^4 + 9*x^5 - 16*x^6 + x^7 + x^8). - Colin Barker, Jan 06 2019
EXAMPLE
Some solutions for n=4:
..3..2..5....3..4..5....1..2..0....3..2..5....1..0..5....1..2..0....1..0..5
..0..1..4....0..1..2....6..3..4....0..1..4....6..3..2....6..5..4....4..3..2
..9..8..6....9.10..7....7..8..5....7.10.11....7..4.11....3..8.11....7..8..6
.12..7.14....6.11..8...12.11.14....6..9..8...10..9..8...12..7.14...12..9.14
.13.10.11...13.14.12....9.10.13...13.14.12...13.14.12....9.10.13...13.10.11
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 09 2015
STATUS
approved