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, May 14 2026: (Start)
a(n) = - 2*a(n-1) - 2*a(n-2) - a(n-3) + a(n-6) + 3*a(n-7) + 4*a(n-8) + 3*a(n-9) + a(n-10) - a(n-13) - 2*a(n-14) - 2*a(n-15) - a(n-16) for n > 18.
G.f.: (-x^18 - 3*x^17 - 2*x^16 + 7*x^15 + 24*x^14 + 47*x^13 + 72*x^12 + 100*x^11 + 127*x^10 + 146*x^9 + 148*x^8 + 137*x^7 + 116*x^6 + 92*x^5 + 66*x^4 + 41*x^3 + 20*x^2 + 7*x + 1)/((x - 1)^2*(x + 1)^2*(x^2 - x + 1)*(x^2 + x + 1)^2*(x^6 + x^5 + x^4 + x^3 + x^2 + x + 1)). (End)
CROSSREFS
KEYWORD
nonn
AUTHOR
Brian Galebach and N. J. A. Sloane, Jun 18 2018
STATUS
approved
