login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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
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, 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
KEYWORD
nonn
AUTHOR
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 25 06:59 EDT 2024. Contains 374586 sequences. (Running on oeis4.)