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A008349 Crystal ball sequence for E_8 lattice.
(Formerly M5419)
3
1, 241, 9361, 131041, 996001, 5109841, 20015281, 64495681, 179375041, 444798001, 1006201681, 2111519521, 4162485601, 7783236241, 13909734001, 23903867521, 39696408961, 63963339121, 100340378641, 153680892001 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

REFERENCES

M. O'Keeffe, Coordination sequences for lattices, Zeit. f. Krist., 210 (1995), 905-908.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n=0..1000

J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (Abstract, pdf, ps).

Index entries for crystal ball sequences

FORMULA

G.f.: (1+232*x+7228*x^2+107224*x^5+133510*x^4+55384*x^3+24508*x^6+232*x^7+x^8)/(1 -x)^9.

MAPLE

57/7*n^8+108/7*n^7+30*n^6+72*n^5+39*n^4+36*n^3+300/7*n^2-24/7*n+1;

CROSSREFS

Sequence in context: A165375 A183887 A007205 * A094732 A119728 A133327

Adjacent sequences:  A008346 A008347 A008348 * A008350 A008351 A008352

KEYWORD

nonn,easy,nice

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com) and J. H. Conway (conway(AT)math.princeton.edu)

EXTENSIONS

The values given O'Keeffe are incorrect.

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.