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%I #21 Apr 10 2018 08:26:35
%S 1,4,11,20,40,68,93,120,157,206,254,299,355,430,495,549,633,735,813,
%T 886,995,1111,1207,1306,1434,1573,1687,1798,1949,2114,2243,2377,2552,
%U 2727,2879,3036,3224,3426,3604,3766,3977,4212,4397,4578,4819,5067,5270,5478
%N Coordination sequence T1 for Scapolite.
%D Inorganic Crystal Structure Database: Collection Code 9502.
%H Sean A. Irvine, <a href="/A008262/b008262.txt">Table of n, a(n) for n = 0..1000</a>
%H R. W. Grosse-Kunstleve, <a href="/A005897/a005897.html">Coordination Sequences and Encyclopedia of Integer Sequences</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 G.f.: -(2*x^27 +3*x^25 +3*x^24 +10*x^23 +20*x^22 +43*x^21 +67*x^20 +114*x^19 +151*x^18 +211*x^17 +257*x^16 +303*x^15 +338*x^14 +354*x^13 +358*x^12 +338*x^11 +305*x^10 +261*x^9 +211*x^8 +155*x^7 +116*x^6 +67*x^5 +45*x^4 +18*x^3 +10*x^2 +3*x +1)*(1 +x)*(-1 +x^2)^2 / (-1 +x^4)^2 / (-1 +x^6) / (-1 +x^7) / (-1 +x^9).
%t Table[SeriesCoefficient[-(2 x^27 + 3 x^25 + 3 x^24 + 10 x^23 + 20 x^22 + 43 x^21 + 67 x^20 + 114 x^19 + 151 x^18 + 211 x^17 + 257 x^16 + 303 x^15 + 338 x^14 + 354 x^13 + 358 x^12 + 338 x^11 + 305 x^10 + 261 x^9 + 211*x^8 + 155 x^7 + 116 x^6 + 67 x^5 + 45 x^4 + 18 x^3 + 10 x^2 + 3 x + 1) (1 + x) (-1 + x^2)^2/(-1 + x^4)^2/(-1 + x^6)/(-1 + x^7)/(-1 + x^9), {x, 0, n}], {n, 0, 47}] (* _Michael De Vlieger_, Dec 23 2015 *)
%K nonn,easy
%O 0,2
%A _Ralf W. Grosse-Kunstleve_