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A009948 Coordination sequence for alpha-Nd, Position Nd1. 0

%I

%S 1,12,42,96,170,264,378,516,674,852,1050,1272,1514,1776,2058,2364,

%T 2690,3036,3402,3792,4202,4632,5082,5556,6050,6564,7098,7656,8234,

%U 8832,9450,10092,10754,11436,12138,12864,13610,14376,15162,15972,16802

%N Coordination sequence for alpha-Nd, Position Nd1.

%D Gmelin Handbook of Inorg. and Organomet. Chem., 8th Ed., 1994, TYPIX search code (194) hP4

%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.

%F Conjectures from _Colin Barker_, Sep 09 2014: (Start)

%F a(n) = (5-(-1)^n+2*(-i)^n+2*i^n+42*n^2)/4 for n>0, where i=sqrt(-1).

%F a(n) = 2*a(n-1)-a(n-2)+a(n-4)-2*a(n-5)+a(n-6) for n>6.

%F G.f.: -(x^6+10*x^5+19*x^4+24*x^3+19*x^2+10*x+1) / ((x-1)^3*(x+1)*(x^2+1)). (End)

%K nonn

%O 0,2

%A R. W. Grosse-Kunstleve (rwgk(AT)cci.lbl.gov)

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Last modified February 19 22:04 EST 2018. Contains 299357 sequences. (Running on oeis4.)