Zamolodchikov periodicity is periodicity of certein recursions associated
with box products X□Y of two finite type Dynkin diagrams. We suggest
an affine analog of Zamolodchikov periodicity, which we call Zamolodchikov
integrability. We conjecture that it holds for products X□Y, where
X is a finite type Dynkin diagram and Y is an extended Dynkin diagram. We
prove this conjecture for the case of Am□A2n−1(1). The proof
employs cluster structures in certain classical rings of invariants, previously
studied by S. Fomin and the author.Comment: 21 pages, 16 figure