Even lattices of rank 9 and determinant 2

Complete list here (see the main page for format details).

• 1 isometry class, mass 1/1393459200.
• 1 possible root systems, see here for statistics of reduced masses for each root system.
• Classified in: M. Kneser, Klassenzahlen definiter quadratischer Formen, Archiv der Math. 8, 241–250 (1957).
• Construction(s): Norm 2/3 vectors in dual of rank 10 even lattices of determinant 3 (unique orbit). Norm 2/7 vectors in dual of rank 10 even lattices of determinant 7. Embeddings of E7 in rank 16 even unimodular lattices.
• Extra information: Lattice \(\#1\) is the \({\rm A}_1 \perp {\rm E}_8\) root lattice.