<image>:

As shown in the figure, it is a pattern composed of squares made with several matchsticks.

(1) Complete the blanks in the table:
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(2) A student arranges matchsticks in the manner shown in the figure above. After finishing the first pattern, he arranges the second, then the third, the fourth, and so on. When he finishes the nth pattern, he has 20 matchsticks left. To complete the (n+1)th pattern, he needs 2 more matchsticks. Which pattern is the last one he arranges?