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

Table of n, a(n) for n=0..40.

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

Conjectures 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

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

STATUS

approved

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Last modified October 25 15:08 EDT 2014. Contains 248556 sequences.