OFFSET
0,2
LINKS
R. W. Grosse-Kunstleve, Table of n, a(n) for n = 0..1000
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 + 4*x + 9*x^2 + 16*x^3 + 28*x^4 + 28*x^5 + 26*x^6 + 7*x^7 - x^9 + 2*x^11) / (1 - x^3)^3.
CROSSREFS
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Mar 18 2018
STATUS
approved