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A009930
Coordination sequence for MgCu2, Cu position.
1
1, 12, 50, 110, 216, 356, 528, 704, 968, 1230, 1514, 1838, 2276, 2562, 3074, 3540, 3998, 4490, 5244, 5570, 6374, 7052, 7662, 8300, 9438, 9740, 10862, 11754, 12512, 13280, 14852, 15060, 16544, 17658, 18542, 19418, 21492, 21542, 23414, 24752
OFFSET
0,2
REFERENCES
Gmelin Handbook of Inorg. and Organomet. Chem., 8th Ed., 1994, TYPIX search code (227) cF24
FORMULA
From Colin Barker, Feb 13 2018: (Start)
G.f.: (1 + 15*x + 90*x^2 + 309*x^3 + 752*x^4 + 1411*x^5 + 2129*x^6 + 2610*x^7 + 2601*x^8 + 2095*x^9 + 1340*x^10 + 643*x^11 + 210*x^12 + 31*x^13 - 7*x^14 - 4*x^15) / ((1 - x)^3*(1 + x)^3*(1 + x^2)*(1 + x + x^2)^3).
a(n) = -3*a(n-1) - 4*a(n-2) - a(n-3) + 6*a(n-4) + 11*a(n-5) + 9*a(n-6) - 9*a(n-8) - 11*a(n-9) - 6*a(n-10) + a(n-11) + 4*a(n-12) + 3*a(n-13) + a(n-14) for n>15.
(End)
CROSSREFS
Sequence in context: A009937 A009932 A009933 * A066644 A009934 A009927
KEYWORD
nonn
STATUS
approved