OFFSET
1,7
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = a(n-3) + a(n-4) + 2*a(n-5) - a(n-9) - a(n-10).
Empirical g.f.: x^2*(1 - x)*(1 + x + 2*x^2 + 2*x^3 + 2*x^4 + 2*x^5 + x^6) / (1 - x^3 - x^4 - 2*x^5 + x^9 + x^10). - Colin Barker, Jan 08 2019
EXAMPLE
All solutions for n=4:
..1..5..3..4..8
..6..7..0..9..2
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 18 2015
STATUS
approved