Hi,
Assuming the fields are numerically ordered ( Field1, Field2, Field3), and that Field1 is the starting field you could use script something like
var startFieldValue = this.getField("Field1").value;
for ( var i = 2; i < 10; i++)
{
startFieldValue++;
this.getField ("Field" + i).value = startFieldValue;
}
This will add 1 to the value of Field1, and then push that value to the next field in the sequence.
The code could probably be added to the validate function of "Field1".
Note: there is no checking that the user actually entered a number in the field, which may be required if you haven't applied any validation to the field.
Hope this helps
Malcolm