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A023910 Theta series of A_19 lattice. 0
1, 380, 29070, 782040, 9438440, 62953992, 293878320, 1095681360, 3397527180, 9278730940, 22633815436, 51077966760, 106592778180, 211336265080, 395232580440, 713167271184, 1229503440980, 2066616183960, 3346158684430, 5318821052280, 8194315251672, 12453539176080 (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..21.

MATHEMATICA

terms = 18; f[q_] = LatticeData["A19", "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

Cf. A023902.

Sequence in context: A188307 A214145 A185493 * A035845 A028682 A222163

Adjacent sequences:  A023907 A023908 A023909 * A023911 A023912 A023913

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

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

More terms from Sean A. Irvine, Jun 12 2019

STATUS

approved

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Last modified September 20 22:45 EDT 2021. Contains 347596 sequences. (Running on oeis4.)