//完全数判断函数
function IsPerfectNum(i:LongInt):Boolean ;
var
sum,k:LongInt;
begin
sum:=1;
for k:= 2 to i div 2 do
if i mod k=0 then sum:=sum+k;
if i=sum then
Result:= true
else
Result:=false;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
idx: Integer;
begin
for idx := 2 to 1000 do
begin
if IsPerfectNum(idx) then
begin
Memo.Lines.Add(IntToStr(idx));
end;
end;
end;
输出：
6
28
496