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A009956 Coordination sequence for FeS2-Pyrite, S position. 1
1, 4, 18, 37, 70, 105, 169, 206, 292, 343, 469, 513, 664, 719, 919, 958, 1186, 1233, 1519, 1541, 1858, 1885, 2269, 2262, 2680, 2675, 3169, 3121, 3652, 3603, 4219, 4118, 4774, 4669, 5419, 5253, 6046, 5873, 6769, 6526, 7468, 7215, 8269, 7937, 9040 (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

Sean A. Irvine, Table of n, a(n) for n = 0..1000

R. W. Grosse-Kunstleve, Coordination Sequences and Encyclopedia of Integer Sequences

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.

Sean A. Irvine, Generating Functions for Coordination Sequences of Zeolites, after Grosse-Kunstleve, Brunner, and Sloane

Index entries for linear recurrences with constant coefficients, signature (0,1,0,2,0,-2,0,-1,0,1).

FORMULA

From Colin Barker, Feb 13 2018: (Start)

G.f.: (1 + 4*x + 17*x^2 + 33*x^3 + 50*x^4 + 60*x^5 + 65*x^6 + 35*x^7 + 20*x^8 + 5*x^9 - 4*x^10 + x^11 + x^12) / ((1 - x)^3*(1 + x)^3*(1 + x^2)^2).

a(n) = a(n-2) + 2*a(n-4) - 2*a(n-6) - a(n-8) + a(n-10) for n>12.

(End)

MATHEMATICA

LinearRecurrence[{0, 1, 0, 2, 0, -2, 0, -1, 0, 1}, {1, 4, 18, 37, 70, 105, 169, 206, 292, 343, 469, 513, 664}, 50] (* Harvey P. Dale, Jun 12 2019 *)

CROSSREFS

Sequence in context: A110621 A124978 A031081 * A031303 A062235 A336630

Adjacent sequences:  A009953 A009954 A009955 * A009957 A009958 A009959

KEYWORD

nonn

AUTHOR

Ralf W. Grosse-Kunstleve

STATUS

approved

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)