login
A005877
Theta series of cubic lattice with respect to square.
(Formerly M3322)
5
4, 8, 8, 16, 12, 8, 24, 16, 16, 24, 16, 16, 28, 32, 8, 32, 32, 16, 40, 16, 16, 40, 40, 32, 36, 16, 24, 48, 32, 24, 40, 48, 16, 56, 32, 16, 64, 40, 32, 32, 36, 40, 48, 48, 32, 48, 48, 16, 80, 40, 24, 80
OFFSET
0,1
REFERENCES
J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 107.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
G. Nebe and N. J. A. Sloane, Home page for this lattice
FORMULA
a(n) = 4*A045828(n).
MATHEMATICA
terms = 52; QP = QPochhammer; s = 4*(QP[q^2]^3*QP[q^4]^2)/QP[q]^2 + O[q]^terms; CoefficientList[s, q] (* Jean-François Alcover, Jul 05 2017 *)
CROSSREFS
Cf. A045828.
Sequence in context: A273572 A273779 A114027 * A144174 A256816 A098354
KEYWORD
nonn,easy
STATUS
approved