Minor Agreement of the Day: οἱ

Sometimes the smallest words catch your eye. As in the pericope of Jesus instructing the disciples to make ready for his entry into Jerusalem. Here's a verse with minor agreements in bold:

Matthew 21:6	Mark 11:4	Luke 19:32
πορευθέντες δὲ οἱ μαθηταὶ καὶ ποιήσαντες καθὼς συνέταξεν αὐτοῖς ὁ Ἰησοῦς ...	καὶ ἀπῆλθον καὶ εὗρον πῶλον δεδεμένον πρὸς θύραν ἔξω ἐπὶ τοῦ ἀμφόδου καὶ λύουσιν αὐτόν.	ἀπελθόντες δὲ οἱ ἀπεσταλμένοι εὗρον καθὼς εἶπεν αὐτοῖς.
And the disciples, going and doing just as Jesus had directed them, ...	And they went away and found a colt tied near a door, outside in the street.	And going away the ones who were sent found it just as he had told them.

Oddly, it's οἱ that caught my eye. Luke on the whole is following Mark in this story, but the occassional dash of Lukan/Matthean agreement is interesting, particularly that both provide the substantive plural nominative article to match up with the participles in the opening structure. Am I really to believe that Luke and Matthew provided the article independently? Both have taken Mark's finite verbals and transformed them into participles. I mean Luke's first verb looks like: Mark's ἀπῆλθον + Matthew's πορευθέντες = Luke's ἀπελθόντες.

P.S. "of the day" does not necessarily mean every day.