OFFSET
0,2
COMMENTS
Note that there may be other vertices in the Galebach list of u-uniform tilings with u <= 6 that have this same coordination sequence. See the Galebach link for the complete list of A-numbers for all these tilings.
LINKS
FORMULA
Conjectures from Chai Wah Wu, Feb 14 2020: (Start)
a(n) = a(n-3) + a(n-9) - a(n-12) for n > 12.
G.f.: (x^12 + 4*x^11 + 9*x^10 + 12*x^9 + 14*x^8 + 14*x^7 + 13*x^6 + 14*x^5 + 14*x^4 + 12*x^3 + 9*x^2 + 4*x + 1)/(x^12 - x^9 - x^3 + 1). (End)
CROSSREFS
KEYWORD
nonn
AUTHOR
Brian Galebach and N. J. A. Sloane, Jun 18 2018
STATUS
approved