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A009955
Coordination sequence for FeS2-Marcasite, Fe position.
1
1, 6, 16, 40, 60, 106, 134, 206, 236, 340, 368, 506, 530, 706, 720, 940, 940, 1206, 1190, 1506, 1468, 1840, 1776, 2206, 2114, 2606, 2480, 3040, 2876, 3506, 3302, 4006, 3756, 4540, 4240, 5106, 4754, 5706, 5296, 6340, 5868, 7006, 6470, 7706, 7100
OFFSET
0,2
REFERENCES
Gmelin Handbook of Inorg. and Organomet. Chem., 8th Ed., 1994, TYPIX search code (58) oP6
FORMULA
From Colin Barker, Feb 13 2018: (Start)
G.f.: (1 + 7*x + 20*x^2 + 41*x^3 + 50*x^4 + 41*x^5 + 20*x^6 + 7*x^7 + x^8) / ((1 - x)^3*(1 + x)^3*(1 + x + x^2)).
a(n) = -a(n-1) + 2*a(n-2) + 3*a(n-3) - 3*a(n-5) - 2*a(n-6) + a(n-7) + a(n-8) for n>8.
(End)
CROSSREFS
Sequence in context: A068941 A130902 A300371 * A160255 A213667 A123205
KEYWORD
nonn
STATUS
approved