F u  = w z u   + ∑ j ≠ i , k   max ⁡  v ∈ V j        w u v         ( 4 )    MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaacqWGgbGrdaWgaaWcbaGaemyDauhabeaakiabg2da9iabdEha3naaBaaaleaacqWG6bGEcqWG1bqDaeqaaOGaey4kaSYaaabuaeaadaWfqaqaaiGbc2gaTjabcggaHjabcIha4bWcbaGaemODayNaeyicI4SaemOvay1aaSbaaWqaaiabdQgaQbqabaaaleqaaaqaaiabdQgaQjabgcMi5kabdMgaPjabcYcaSiabdUgaRbqab0GaeyyeIuoakiabbccaGiabdEha3naaBaaaleaacqWG1bqDcqWG2bGDaeqaaOGaaCzcaiaaxMaadaqadiqaaiabisda0aGaayjkaiaawMcaaaaa@5212@