Public Class Form1
    Dim a, b, suma, n As Integer

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        a = 1
        b = 0
        n = TextBox1.Text
        RichTextBox1.Text = " "
        If n = 0 Then
            Label1.Text = 0
            RichTextBox1.Text = " "
        ElseIf n = 1 Then
            Label1.Text = 0
            RichTextBox1.Text = "0,"
        ElseIf n = 2 Then
            Label1.Text = 1
            RichTextBox1.Text = "0,1"
        Else
            RichTextBox1.Text = "0,1"
            For i As Integer = 3 To n
                suma = a + b
                Label1.Text = suma
                RichTextBox1.Text += "," + Label1.Text
                b = a
                a = suma

            Next
        End If
        


    End Sub
End Class