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A023913 Theta series of A_22 lattice. 0
1, 506, 53130, 2029566, 35668446, 340000122, 2094317302, 9773190636, 37179208176, 120683024506, 346388200466, 897628047384, 2144673537006, 4770315795938, 10019792884332, 19955152642348, 38085959774742 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

REFERENCES

J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 110.

LINKS

Table of n, a(n) for n=0..16.

MATHEMATICA

terms = 17; f[q_] = LatticeData["A22", "ThetaSeriesFunction"][-I*Log[q]/Pi]; s =

f[q] + O[q]^(2 terms); Partition[CoefficientList[s, q] // Round, 2][[All, 1]][[1 ;; terms]] (* Jean-Fran├žois Alcover, Jul 06 2017 *)

CROSSREFS

Sequence in context: A295992 A122267 A204946 * A035848 A028685 A152524

Adjacent sequences:  A023910 A023911 A023912 * A023914 A023915 A023916

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Robert.Harley(AT)inria.fr, see A023902.

STATUS

approved

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Last modified January 18 01:10 EST 2022. Contains 350410 sequences. (Running on oeis4.)