OFFSET
1,1
COMMENTS
Column 4 of A223692.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 59*a(n-1) - 1103*a(n-2) + 7621*a(n-3) - 16900*a(n-4).
Empirical g.f.: 144*x*(3 - 91*x + 760*x^2 - 1856*x^3) / (1 - 59*x + 1103*x^2 - 7621*x^3 + 16900*x^4). - Colin Barker, Aug 22 2018
EXAMPLE
Some solutions for n=3:
..6.14..6.14....0..8.10..2....4..5..4..3....6..7.15.13....2.10.12.14
..6.14..6..7...10..2.10..8....4..3.11.13...15..9.11..3...12.14..8..0
..6..7.15..9...10..8.10..2...11..9.15..7...15.13.11..9....8.10..8.14
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 25 2013
STATUS
approved