Question

VB 数列的前三位是123,以后一项为前三项之和,求25位到三十位之和

Answer 1

Private Sub Command1_Click()

Dim a As String, b As String, c, x As Long, sum As Long, sum1 As Long

a = "1 2 3"

b = a

For i = 1 To 27

c = Split(b)

For j = 0 To UBound(c)

x = x + c(j)

Next

a = a & " " & x

b = Mid(b, InStr(b, " ") + 1) & " " & x

If i >= 22 Then sum = sum + x

x = 0

Next

Debug.Print a

Debug.Print sum '25项至30项之和

a = Replace(a, " ", "")

Debug.Print a

For i = 25 To 30

sum1 = sum1 + Mid(a, i, 1)

Next

Debug.Print sum1 '25位到30位之和

End Su