A311666 - OEIS

%I #7 Jun 07 2024 02:04:54

%S 1,4,8,13,14,21,28,30,38,35,40,45,52,60,64,63,62,71,76,84,94,89,90,93,

%T 102,108,118,119,116,121,124,134,142,143,146,147,152,156,168,167,170,

%U 177,178,184,190,193,194,201,208,210

%N Coordination sequence Gal.4.108.1 where Gal.u.t.v denotes the coordination sequence for a vertex of type v in tiling number t in the Galebach list of u-uniform tilings.

%C 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.

%H Brian Galebach, <a href="/A250120/a250120.html">k-uniform tilings (k <= 6) and their A-numbers</a>

%F Conjectures from _Chai Wah Wu_, Jun 06 2024: (Start)

%F a(n) = a(n-6) + a(n-7) - a(n-13) for n > 15.

%F G.f.: (-2*x^15 + 3*x^13 + 3*x^12 + 10*x^11 + 13*x^10 + 14*x^9 + 26*x^8 + 25*x^7 + 27*x^6 + 21*x^5 + 14*x^4 + 13*x^3 + 8*x^2 + 4*x + 1)/(x^13 - x^7 - x^6 + 1). (End)

%K nonn

%O 0,2

%A _Brian Galebach_ and _N. J. A. Sloane_, Jun 18 2018