Question

编写程序计算并输出下面数列前n项的和,当第一次出现和数的绝对值大于500时求和终止.

Answer 1

Private Sub Form_Click()

Dim n As Integer,s As Integer

n = 0

s = 0

Do While 1

n = n + 1

s = s + (-1) ^ (n - 1) * n * (n + 1) * (n + 2)

Print n,(-1) ^ (n - 1) * n * (n + 1) * (n + 2)

If Abs(s) > 500 Then

Exit Do

End If

Loop

Print

Print "s=",s

End Sub