A029682 Theta series of quadratic form with Gram matrix [ 2, 1, 0; 1, 2, 1; 0, 1, 4 ].

1, 6, 6, 12, 18, 0, 12, 24, 18, 18, 6, 24, 24, 24, 12, 8, 42, 12, 30, 48, 0, 24, 36, 24, 36, 6, 12, 48, 60, 24, 0, 48, 42, 24, 36, 12, 54, 48, 12, 48, 18, 24, 24, 84, 48, 0, 60, 24, 48, 42, 6, 72, 72, 24, 48, 0, 36, 48, 60, 48, 20, 48, 24, 72, 90, 12, 24, 108, 36, 24, 0, 48, 90, 60

Offset

0,2

Comments

This is the trigonal R lattice (the even holotype) of dimension 3.

Links

John Cannon, Table of n, a(n) for n = 0..5000

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

Example

1 + 6*q^2 + 6*q^4 + 12*q^6 + 18*q^8 + 12*q^12 + 24*q^14 + 18*q^16 + 18*q^18 + ...

Crossrefs

Sequence in context: A046625 A315787 A309458 * A014201 A315788 A315789

Adjacent sequences: A029679 A029680 A029681 * A029683 A029684 A029685

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved