Before revision:  Using this algorithm  , we show that in the limit of a large lattice the two chains phase separate , in contradiction with the ideal chain behaviour predicted by the Flory theorem .
After revision:  Using this algorithm for chains of length up to 40 000 monomers and aspect ratios 1 <= r <= 10 , we show that in the limit of a large lattice the two chains phase separate , in contradiction with the ideal chain behaviour predicted by the Flory theorem .