Stewart made 4 of 5 3-pointers. Freshman Tamar Bates scored 10 points off the bench for the Hoosiers (4-0).
Indiana's preseason All-American Trayce Jackson-Davis, who averages 19.3 points and 10.3 rebounds per game, played 19 minutes and had 11 points and seven rebounds.
Jordan Brown led Louisiana (3-1) with 10 points and Theo Akwuba added nine points and 10 rebounds.
At one point in the first half, Louisiana had made 2 of 29 shots (7%) and trailed 29-4. Indiana led 39-14 at halftime.
The Ragin' Cajuns were outscored only 39-30 in the second half and 27 Indiana turnovers helped keep the game from getting completely out of hand.
For the game, Louisiana shot 19%, made 2 of 20 3-point tries, and just 14 of 24 free throws.
Indiana shot 59% and made 10 of 19 3-pointers along with 10 of 13 free throws.
Indiana will play three games in seven days of their annual Hoosier Classic. They play Jackson State on Tuesday and Marshall on Saturday.
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