∫01/2E2⁢n⁡(t)⁢ⅆ⁡t=-E2⁢n+1⁡(0)2⁢n+1=2⁢(22⁢n+2-1)⁢B2⁢n+2(2⁢n+1)⁢(2⁢n+2),