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 A009948 Coordination sequence for alpha-Nd, Position Nd1. 1
 1, 12, 42, 96, 170, 264, 378, 516, 674, 852, 1050, 1272, 1514, 1776, 2058, 2364, 2690, 3036, 3402, 3792, 4202, 4632, 5082, 5556, 6050, 6564, 7098, 7656, 8234, 8832, 9450, 10092, 10754, 11436, 12138, 12864, 13610, 14376, 15162, 15972, 16802 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 REFERENCES Gmelin Handbook of Inorg. and Organomet. Chem., 8th Ed., 1994, TYPIX search code (194) hP4. LINKS Sean A. Irvine, 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. FORMULA From Colin Barker, Sep 09 2014: (Start) a(n) = (5-(-1)^n+2*(-i)^n+2*i^n+42*n^2)/4 for n>0, where i=sqrt(-1). a(n) = 2*a(n-1)-a(n-2)+a(n-4)-2*a(n-5)+a(n-6) for n>6. 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) CROSSREFS Sequence in context: A210206 A005901 A090554 * A193068 A007586 A228391 Adjacent sequences:  A009945 A009946 A009947 * A009949 A009950 A009951 KEYWORD nonn AUTHOR STATUS approved

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Last modified December 12 00:07 EST 2018. Contains 318052 sequences. (Running on oeis4.)