OFFSET
1,4
COMMENTS
Column 2 of A230513.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..210
FORMULA
Empirical: a(n) = 5*a(n-1) - 4*a(n-2) - 5*a(n-3) + 9*a(n-4) + 12*a(n-5).
Empirical g.f.: 2*x^4*(1 - x) / (1 - 5*x + 4*x^2 + 5*x^3 - 9*x^4 - 12*x^5). - Colin Barker, Mar 17 2018
EXAMPLE
All solutions for n=4:
..0..7....0..1
..1..6....7..2
..2..5....6..3
..3..4....5..4
CROSSREFS
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 21 2013
STATUS
approved