大方廣佛華嚴經疏 55.11

55.11

三會主多少。若以人剋定，唯五十四。若以會顯人，則五十七，文殊分四故。或剎塵數、或無盡無盡，思之。

Third, the number of assembly leaders: If definitively fixed by persons, there are only fifty-four. If revealing persons through assemblies, there are fifty-seven, because Mañjuśrī is divided into four. Or dust motes in a kṣetra, or endless and inexhaustible; reflect on this.