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A056948
Jacobi form of weight 12 and index 1 associated with a nonexistent Niemeier lattice of Coxeter number 1.
1
1, 0, 0, -2, 26, 0, 0, 32560, 130812, 0, 0, 3671562, 9174424, 0, 0, 95675472, 188233758, 0, 0, 1142977594, 1959731160, 0, 0, 8506658544, 13293118872, 0, 0, 45762829976, 67073331776, 0, 0, 195388726752, 272567835540, 0, 0, 698077270836, 938806082418, 0, 0, 2176652437872
OFFSET
0,4
COMMENTS
a(3) < 0 (apparently the only negative term) so the lattice cannot exist.
a(4n) + 2*Sum_{r=1..floor(sqrt(4n))} a(4*n - r^2) = A056947(n).
REFERENCES
Eichler and Zagier, The Theory of Jacobi Forms, Birkhauser 1985
FORMULA
E_8 * E_{4, 1} + (2*h - 60) * E_{12, 1} where h = 1.
a(n) = A055747(n) - 58*A003785(n). - Sean A. Irvine, May 18 2022
CROSSREFS
KEYWORD
sign
AUTHOR
Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), Jul 17 2000
STATUS
approved