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A009957 Coordination sequence for FeS2-Pyrite, Fe position. 1
1, 6, 18, 44, 68, 120, 152, 234, 270, 386, 422, 576, 608, 804, 828, 1070, 1082, 1374, 1370, 1716, 1692, 2096, 2048, 2514, 2438, 2970, 2862, 3464, 3320, 3996, 3812, 4566, 4338, 5174, 4898, 5820, 5492, 6504, 6120, 7226, 6782, 7986, 7478, 8784, 8208 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
REFERENCES
Gmelin Handbook of Inorg. and Organomet. Chem., 8th Ed., 1994, TYPIX search code (205) cP12
LINKS
R. W. Grosse-Kunstleve, G. O. Brunner and N. J. A. Sloane, Algebraic Description of Coordination Sequences and Exact Topological Densities for Zeolites, Acta Cryst., A52 (1996), pp. 879-889.
FORMULA
From Colin Barker, Sep 09 2014: (Start)
a(n) = (13+3*(-1)^n-2*(1+(-1)^n)*n-2*(-18+(-1)^n)*n^2)/8 for n>0.
a(n) = 3*a(n-2)-3*a(n-4)+a(n-6) for n>6.
G.f.: -(x^6+6*x^5+17*x^4+26*x^3+15*x^2+6*x+1) / ((x-1)^3*(x+1)^3). (End)
CROSSREFS
Sequence in context: A272700 A191101 A184630 * A344992 A011929 A070735
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified June 24 00:53 EDT 2024. Contains 373661 sequences. (Running on oeis4.)