A028973 Theta series of quadratic form with Gram matrix [ 7, 1, -3; 1, 3, 1; -3, 1, 7 ].

1, 0, 0, 2, 0, 0, 0, 6, 6, 0, 0, 0, 8, 0, 0, 6, 0, 0, 0, 0, 6, 0, 0, 18, 0, 0, 0, 8, 12, 0, 0, 0, 18, 0, 0, 6, 0, 0, 0, 0, 6, 0, 0, 6, 0, 0, 0, 30, 20, 0, 0, 0, 12, 0, 0, 12, 0, 0, 0, 0, 12, 0, 0, 30, 0, 0, 0, 6, 24, 0, 0, 0, 18, 0, 0, 2, 0, 0, 0, 0, 18, 0, 0, 18, 0, 0, 0, 36, 12, 0, 0, 0