Preheat oven to 350 degrees F (175 degrees C). Spray or grease one 9x13 inch pan.
Reserve 1 cup cake mix. In a large bowl, combine the remaining dry cake mix with 1 egg and 1/2 cup melted butter. Mix well, and then pat into prepared pan.
In a large bowl, mix together the pumpkin, 3 eggs, 1/2 cup white sugar, brown sugar, and cinnamon. Pour over crust.