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.
Conjectures: for k >= 1, a(7*k-1) = a(7*k) = 28 + (k-1)*30 and a(7*k+1) = a(7*k+2) = 36 + (k-1)*30. - Bernard Schott, Dec 24 2019
LINKS
FORMULA
Conjectures from Chai Wah Wu, Dec 24 2019: (Start)
a(n) = a(n-1) + a(n-7) - a(n-8) for n > 9.
G.f.: (-2*x^9 + 5*x^8 - x^7 + 7*x^6 + 4*x^5 + 3*x^4 + 8*x^3 + 2*x^2 + 3*x + 1)/(x^8 - x^7 - x + 1). (End)
CROSSREFS
KEYWORD
nonn
AUTHOR
Brian Galebach and N. J. A. Sloane, Jun 18 2018
STATUS
approved