Of Jeduthun: the sons of Jeduthun; Gedaliah, and Zeri, and Jeshaiah, Hashabiah, and Mattithiah, six, under the hands of their father Jeduthun, who prophesied with a harp, to give thanks and to praise the Lord. (1 Chronicles 25:3)
Six.
 Only 5 names are here listed. The list in vs. 9-31 suggests that the missing name is Shimei of v. 17 (see on v. 9). The LXX includes the name Shimei, placing it 4th in the list.
Who prophesied.
 See on v. 1.