OFFSET
1,1
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 19*a(n-1) +16*a(n-2) for n>3.
Empirical g.f.: x*(34 - 41*x + 61*x^2) / (1 - 19*x - 16*x^2). - Colin Barker, Jan 04 2019
EXAMPLE
Some solutions for n=3:
..0..1..8..9..4....6..8..9..3..4....6..1..8..9..4....0..8..9..3..4
..5..6.14..2..3...12..0.14..1..2...11..0..7..2..3....5..6.13..1..2
.16.17.12.13..7...16..5.18.13..7...10..5.18.19.14...17.11.19..7.14
.15.10.11.18.19...15.10.17.11.19...15.16.17.12.13...15.16.10.18.12
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 02 2015
STATUS
approved