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A006910
Theta series of laminated lattice LAMBDA_11^{min}.
(Formerly M5452)
1
1, 0, 432, 1632, 8700, 18048, 51072, 82880, 191926, 251648, 517568, 619104, 1204024, 1322368, 2326528, 2515904, 4396188, 4407552, 7238000, 7303456, 11911352, 11434752, 17948288, 17151936, 27144744, 25129984, 37714368, 35413888, 54674928, 48607872, 72122368
OFFSET
0,3
COMMENTS
Theta series is an element of the space of modular forms on Gamma_1(32) with Kronecker character 8 in modulus 32, weight 11/2, and dimension 22 over the integers. - Andy Huchala, May 05 2023
REFERENCES
J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 157.
E. C. Pervin, personal communication.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
PROG
(Magma)
prec := 40;
S := SymmetricMatrix([4, 2, 4, 0, -2, 4, 0, -2, 0, 4, 0, 0, -2, 0, 4, -2, -2, 0, 0, 0, 4, 0, 0, 0, 0, 0, -2, 4, 0, 0, 0, 0, 0, 0, -2, 4, 0, 0, 0, 0, 1, -1, 0, 0, 4, 0, 0, 0, 0, -1, 0, 0, 0, 0, 4, -1, -2, 1, 1, 0, 1, 0, -1, 0, 1, 4]);
L := LatticeWithGram(S);
T<q> := ThetaSeries(L, 45);
M := ThetaSeriesModularFormSpace(L);
B := Basis(M, prec);
Coefficients(&+[Coefficients(T)[2*i-1] * B[i] : i in [1..21]] + Coefficients(T)[45]*B[22]); // Andy Huchala, May 05 2023
CROSSREFS
Sequence in context: A179666 A203663 A250815 * A015229 A360840 A248460
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(26)-a(30) from Andy Huchala, May 05 2023
STATUS
approved