OT-PROPHET.filter - rsv twenty-one:

rsv@Jeremiah:52:1 @ Zedeki'ah was twenty-one years old when he became king; and he reigned eleven years in Jerusalem. His mother's name was Hamu'tal the daughter of Jeremiah of Libnah.

rsv@Daniel:10:13 @ The prince of the kingdom of Persia withstood me twenty-one days; but Michael, one of the chief princes, came to help me, so I left him there with the prince of the kingdom of Persia