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A315615
Coordination sequence Gal.6.609.6 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.
1
1, 6, 12, 15, 18, 21, 24, 33, 42, 45, 48, 51, 54, 57, 60, 72, 84, 84, 84, 87, 90, 93, 96, 111, 126, 123, 120, 123, 126, 129, 132, 150, 168, 162, 156, 159, 162, 165, 168, 189, 210, 201, 192, 195, 198, 201, 204, 228, 252, 240
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.
FORMULA
From Chai Wah Wu, Dec 20 2019: (Start)
a(n) = 2*a(n-1) - 3*a(n-2) + 4*a(n-3) - 5*a(n-4) + 6*a(n-5) - 7*a(n-6) + 8*a(n-7) - 7*a(n-8) + 6*a(n-9) - 5*a(n-10) + 4*a(n-11) - 3*a(n-12) + 2*a(n-13) - a(n-14) for n > 14 (conjectured).
G.f.: (x^14 + 4*x^13 + 3*x^12 + 5*x^11 + 5*x^10 + 6*x^9 + 7*x^8 + 13*x^7 + 7*x^6 + 6*x^5 + 5*x^4 + 5*x^3 + 3*x^2 + 4*x + 1)/((x - 1)^2*(x^2 + 1)^2*(x^4 + 1)^2) (conjectured). (End)
CROSSREFS
Sequence in context: A141698 A306711 A290965 * A315616 A091011 A324771
KEYWORD
nonn
AUTHOR
STATUS
approved