お世話になっております。
現在アプリを開発中ですが、何しろ知識がないため、いろいろなところでつまずいています。
今回の質問は、下記のコード（同じことを２５回繰り返します）を配列（Arrayなど)を使ってすっきりとさせたいことです。
一行つづ書いていけば一応完成はするのですが、ビルドして走らせてみると、このページだげ、動きがカクカクしていてスムーズに動きません。
コードがすっきりすればカクカクもなくなるとおもいます。
ググッて見てあれこれと試してはいますが、なかなか動いてくれません。
よろしくお願いします。

btn2 = UIButton()
btn3 = UIButton()
btn4 = UIButton()
btn5 = UIButton()
btn6 = UIButton()
btn7 = UIButton()
btn8 = UIButton()
btn9 = UIButton()
btn10 = UIButton()
btn11 = UIButton()
btn12 = UIButton()
btn13 = UIButton()
btn14 = UIButton()
btn15 = UIButton()
btn16 = UIButton()
btn17 = UIButton()
btn18 = UIButton()
btn19 = UIButton()
btn20 = UIButton()
btn21 = UIButton()
btn22 = UIButton()
btn23 = UIButton()
btn24 = UIButton()
btn25 = UIButton()

btn1.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn2.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn3.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn4.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn5.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn6.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn7.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn8.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn9.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn10.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn11.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn12.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn13.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn14.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn15.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn16.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn17.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn18.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn19.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn20.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn21.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn22.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn23.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn24.frame = CGRectMake(0,0,buttonWidth,buttonHeight)
btn25.frame = CGRectMake(0,0,buttonWidth,buttonHeight)

btn1.layer.masksToBounds = true
btn2.layer.masksToBounds = true
btn3.layer.masksToBounds = true
btn4.layer.masksToBounds = true
btn5.layer.masksToBounds = true
btn6.layer.masksToBounds = true
btn7.layer.masksToBounds = true
btn8.layer.masksToBounds = true
btn9.layer.masksToBounds = true
btn10.layer.masksToBounds = true
btn11.layer.masksToBounds = true
btn12.layer.masksToBounds = true
btn13.layer.masksToBounds = true
btn14.layer.masksToBounds = true
btn15.layer.masksToBounds = true
btn16.layer.masksToBounds = true
btn17.layer.masksToBounds = true
btn18.layer.masksToBounds = true
btn19.layer.masksToBounds = true
btn20.layer.masksToBounds = true
btn21.layer.masksToBounds = true
btn22.layer.masksToBounds = true
btn23.layer.masksToBounds = true
btn24.layer.masksToBounds = true
btn25.layer.masksToBounds = true
btn1.layer.cornerRadius = 2.0

btn2.layer.cornerRadius = 2.0
btn3.layer.cornerRadius = 2.0
btn4.layer.cornerRadius = 2.0
btn5.layer.cornerRadius = 2.0
btn6.layer.cornerRadius = 2.0
btn7.layer.cornerRadius = 2.0
btn8.layer.cornerRadius = 2.0
btn9.layer.cornerRadius = 2.0
btn10.layer.cornerRadius = 2.0
btn11.layer.cornerRadius = 2.0
btn12.layer.cornerRadius = 2.0
btn13.layer.cornerRadius = 2.0
btn14.layer.cornerRadius = 2.0
btn15.layer.cornerRadius = 2.0
btn16.layer.cornerRadius = 2.0
btn17.layer.cornerRadius = 2.0
btn18.layer.cornerRadius = 2.0
btn19.layer.cornerRadius = 2.0
btn20.layer.cornerRadius = 2.0
btn21.layer.cornerRadius = 2.0
btn22.layer.cornerRadius = 2.0
btn23.layer.cornerRadius = 2.0
btn24.layer.cornerRadius = 2.0
btn25.layer.cornerRadius = 2.0