OFFSET
1,1
COMMENTS
The 1 X n, 2 X n, 3 X n versions satisfied recurrence relations of degrees 2, 3, 4 respectively, but I have done quite a lot of LLL work and failed to find a degree-5 relation for this one.
LINKS
R. H. Hardin, Table of n, a(n) for n = 1..212
Sean A. Irvine, Java program (github)
FORMULA
Empirical: a(n)=3*a(n-1)+12*a(n-2)+a(n-3)-58*a(n-4)-115*a(n-5)+83*a(n-6)+312*a(n-7)+120*a(n-8)-336*a(n-9)-348*a(n-10)+420*a(n-11)+104*a(n-12)-194*a(n-13)+43*a(n-14)+35*a(n-15)-42*a(n-16)-3*a(n-17)+14*a(n-18)-a(n-19)-a(n-20) - R. H. Hardin, Jan 01 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Tom Womack (tom(AT)womack.net)
STATUS
approved