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%I #16 Apr 10 2018 08:26:35
%S 1,4,12,30,52,80,116,156,204,258,318,384,458,536,622,714,812,916,1028,
%T 1144,1268,1398,1534,1676,1826,1980,2142,2310,2484,2664,2852,3044,
%U 3244,3450,3662,3880,4106,4336,4574,4818,5068,5324,5588,5856,6132,6414,6702
%N Coordination sequence for quartz.
%D Inorganic Crystal Structure Database: Collection Code 31048.
%H Sean A. Irvine, <a href="/A008261/b008261.txt">Table of n, a(n) for n = 0..1000</a>
%H R. W. Grosse-Kunstleve, G. O. Brunner and N. J. A. Sloane, <a href="http://neilsloane.com/doc/ac96cs/">Algebraic Description of Coordination Sequences and Exact Topological Densities for Zeolites</a>, Acta Cryst., A52 (1996), pp. 879-889.
%H Sean A. Irvine, <a href="/A008000/a008000_1.pdf">Generating Functions for Coordination Sequences of Zeolites, after Grosse-Kunstleve, Brunner, and Sloane</a>
%F a(6m)=114m^2+2, a(6m+1)=114m^2+38m+4, a(6m+2)=114m^2+76m+14 (m>0), a(6m+3)=114m^2+114m+30, a(6m+4)=114m^2+152m+52, a(6m+5)=114m^2+190m+80 (_N. J. A. Sloane_).
%p (1+3*x+7*x^2+14*x^3+11*x^4+3*x^5-x^6-2*x^7+2*x^8)/(1-x^3)/(1-x^2)/(1-x);
%K nonn,easy
%O 0,2
%A _Ralf W. Grosse-Kunstleve_