Lionel has enough Graham crackers to make 14/2 = <<14/2=7>>7 Oreo cheesecakes
Lionel has enough Oreos to make 15/3 = <<15/3=5>>5 Oreo cheesecakes
Therefore, the maximum number of cheesecakes Lionel can make is 5.
Lionel needs 2 * 5 = <<2*5=10>>10 boxes of Graham crackers to make 4 cheesecakes
He'll have 14 - 10 = <<14-10=4>>4 boxes left over
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