A detailed picture of the mechanism of homologous recombination has been gathered over the years, but deciphering how homologues get together in the first place has been far more elusive. The ...

For a first-order formula φ (x; y) we introduce and study the characteristic sequence P n : n < ω of hypergraphs defined by P n (y₁…., y n ):= $ (\exists x)\bigwedge _ {i\leq n}\varphi (x;y_ {i})$ .