php - I want to add the set of the first number that is sent using input with the second value that is sent by input.with one input

one text

    $sum = 0;
    for ($i = $_GET["value"] ; $i < 10 ; $i--){
    
       
           $sum = $i + $sum;

    }
    echo $sum;
    ?>
    <form action="" method="get">
        <input type="text" name="value">

        <button type="submit" name="sender" id="sender">
            sender
        </button>
    </form>

if i send 1 in first time with input it shold echo 1 and if i send 4 in secound time it shold echo 5