OFFSET
0,2
LINKS
R. W. Grosse-Kunstleve, 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
International Zeolite Association, Database of Zeolite Structures
FORMULA
G.f.: (1 + x) * (1 + 4*x + 11*x^2 + 24*x^3 + 42*x^4 + 64*x^5 + 84*x^6 + 97*x^7 + 101*x^8 + 98*x^9 + 84*x^10 + 63*x^11 + 42*x^12 + 25*x^13 + 10*x^14 + x^15 - x^16 + x^17 + 2*x^18 + x^19) / ((1 - x)^3 * (1 + x + x^2)^2 * (1 + x + x^2 + x^3 + x^4) * (1 + x + x^2 + x^3 + x^4 + x^5 + x^6)). - Colin Barker, Dec 20 2015
G.f.: (1 + 4*x + 10*x^2 + 20*x^3 + 31*x^4 + 40*x^5 + 42*x^6 + 33*x^7 + 17*x^8 + x^9 - 17*x^10 - 35*x^11 - 42*x^12 - 38*x^13 - 32*x^14 - 24*x^15 - 11*x^16 + 3*x^18 - 2*x^20 - x^21) / (1 - x^3)^2 / (1 - x^5) / (1 - x^7). - Sean A. Irvine, Mar 15 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved