| T r  ∩ T ′  r  | = ∑ i  ∑ j  | F i  ∩ G j  | = ∑ i  | F i  ∩ G | = ∑ j  | F ∩ G j  | ,               ( 15  )    MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaacqGG8baFcqWGubavdaWgaaWcbaGaemOCaihabeaakiabgMIihlqbdsfauzaafaWaaSbaaSqaaiabdkhaYbqabaGccqGG8baFcqGH9aqpdaaeqbqaamaaqafabaGaeiiFaWNaemOray0aaSbaaSqaaiabdMgaPbqabaGccqGHPiYXcqWGhbWrdaWgaaWcbaGaemOAaOgabeaakiabcYha8jabg2da9maaqafabaGaeiiFaWNaemOray0aaSbaaSqaaiabdMgaPbqabaGccqGHPiYXcqWGhbWrcqGG8baFcqGH9aqpdaaeqbqaaiabcYha8jabdAeagjabgMIihlabdEeahnaaBaaaleaacqWGQbGAaeqaaOGaeiiFaWNaeiilaWcaleaacqWGQbGAaeqaniabggHiLdaaleaacqWGPbqAaeqaniabggHiLdaaleaacqWGQbGAaeqaniabggHiLdaaleaacqWGPbqAaeqaniabggHiLdGccaWLjaGaaCzcamaabmGabaGaeGymaeJaeGynaudacaGLOaGaayzkaaaaaa@6853@