login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A006916 Theta series of laminated lattice LAMBDA_13^{mid}.
(Formerly M5484)
1
1, 0, 890, 6400, 36600, 110080, 337520, 698880, 1649610, 2780160, 5619792, 8387840, 15347280, 20974080, 35834560, 46174720, 74480280, 92062720, 142597450, 169132800, 254916880, 293647360, 429515280, 485235200, 693838000, 765358080, 1078906000, 1170170880 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
Theta series is an element of the space of modular forms on Gamma_1(8) with Kronecker character 8, weight 13/2, and dimension 7 over the integers. - Andy Huchala, May 04 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).
LINKS
G. Nebe and N. J. A. Sloane, Home page for this lattice
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, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, 4, 0, 1, -2, 0, 1, 0, 0, -1, 1, 0, 0, 4, -1, 0, -1, -1, 1, 0, 1, 0, 1, 1, 0, 0, 4]);
L := LatticeWithGram(S);
T<q> := ThetaSeries(L, 14);
M := ThetaSeriesModularFormSpace(L);
B := Basis(M, prec);
Coefficients(&+[Coefficients(T)[2*i-1]*B[i] :i in [1..7]]); // Andy Huchala, May 05 2023
CROSSREFS
Sequence in context: A250513 A252577 A202528 * A128871 A110726 A204366
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(11)-a(27) from Andy Huchala, May 05 2023
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 23 20:33 EDT 2024. Contains 371916 sequences. (Running on oeis4.)