In proton-proton collisions there is a smooth transition between the regime
of double parton scattering, initiated by two pairs of partons at a large
relative distance, and the regime where a single parton splits into a parton
pair in one or both protons. We present a scheme for computing both
contributions in a consistent and practicable way.Comment: 5 pages, 3 figures. To appear in the proeceedings of MPI@LHC 2015,
Trieste, Italy, 23-27 November 201