Knight's Sudoku

This new style of puzzle combines elements of Sudoku with the motion of chess pieces.  Every row, column, and three-by-three square must contain exactly three knights.  A numeric clue indicates that there is a knight in that square and indicates the number of other knights that it can attack from that square.  Though these puzzles feel different, these are truly Sudoku, except that three of the numbers are now knights, the other six are now spaces, and there's one additional constraint.

Four of these have already been accepted for publication in the College Math Journal this fall.  I'm posting an easier one here today in an attempt to create some appetite. 

High quality PDF for printing.