Вычисление суммы ряда, программа зациклилась

//---------------------------------------------------------------------------
 
#include <vcl.h>
#pragma hdrstop
#include <math.h>
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button2Click(TObject *Sender)
{
Edit1->Clear();
Edit2->Clear();
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button3Click(TObject *Sender)
{
Close();        
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
int i, w=0; int k;
k=StrToFloat(Edit1->Text);
for(i=-2; i<=k; k++)
{int p=1;
w=w+pow(-1,i)*p/(2*(i-4));}
Edit2->Text=FloatToStr(w);
}
//---------------------------------------------------------------------------