OFFSET
0,2
REFERENCES
Inorganic Crystal Structure Database: Collection Code 67669 (for Moganite)
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
D. M. Teter, G.V. Gibbs, M. B. Boisen, D.C. Allan, and M. P. Teter, First principles study of several hypothetical silica framework structures, Physical Review B, 52 (1995), pp. 8064-8073.
Index entries for linear recurrences with constant coefficients, signature (1,0,2,-2,0,-1,1).
FORMULA
a(3m) = 22m^2+2, a(3m+1) = 22m^2+15m+4, a(3m+2)=22m^2+29m+11. - N. J. A. Sloane
G.f.: -(x+1)*(x^6+2*x^5+5*x^4+6*x^3+5*x^2+2*x+1) / ((x-1)^3*(x^2+x+1)^2). - Colin Barker, Dec 12 2012
MATHEMATICA
CoefficientList[Series[-(x + 1) (x^6 + 2 x^5 + 5 x^4 + 6 x^3 + 5 x^2 + 2 x + 1)/((x - 1)^3 (x^2 + x + 1)^2), {x, 0, 60}], x] (* Vincenzo Librandi, Oct 15 2013 *)
LinearRecurrence[{1, 0, 2, -2, 0, -1, 1}, {1, 4, 11, 24, 41, 62, 90, 122}, 70] (* Harvey P. Dale, May 10 2024 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Ralf W. Grosse-Kunstleve, David M. Teter (dmteter(AT)sandia.gov)
STATUS
approved