A001942 - OEIS

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A001942

Expansion of reciprocal of theta series of Leech lattice.

1, 0, -196560, -16773120, 38237799600, 6589219553280, -7156481189457600, -1928958160910376960, 1281020641484922702000, 496393397255370269491200, -216626064507656630386166880, -118257112035536800684700160000

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

REFERENCES

J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 135.

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..376

G. Nebe and N. J. A. Sloane, Home page for lattice

Eric Weisstein's World of Mathematics, Leech Lattice.

MATHEMATICA

terms = 12; f[q_] = LatticeData["Leech", "ThetaSeriesFunction"][-I Log[q]/Pi]; s = Series[1/f[q], {q, 0, 2 terms}]; CoefficientList[s, q^2][[1 ;; terms]] // Round (* Jean-François Alcover, Jul 07 2017 *)

CROSSREFS

Cf. A008408.

Sequence in context: A179253 A008408 A305920 * A034597 A037148 A323282

Adjacent sequences: A001939 A001940 A001941 * A001943 A001944 A001945

KEYWORD

sign

AUTHOR

N. J. A. Sloane

STATUS

approved