The above were helpful in telling you it was BS but they didn't tell you why it was BS. I think you might be confusing two rules of thumb.
Your target speed on final will be a function of your weight. Robin747 is close to the mark - take a look in your QRH or POH and look at airspeed suspect/erratic checklists and tables.
You may be able to come up with a quick calculation that gives an approximate N1 setting for your weight (not speed). We had one in the BAe146-300, it was something like "landing weight plus three take two." Eg, landing weight 36 tonnes. Add "three". 66. Take "two." 64. So set 64%N1 as target for a normal landing at 36 tonnes.
Take a look at your aircraft's tables and see if you can spot a similar relationship.
As for your factoring in groundspeed for your N1 -- don't know why you would be interested in doing this. The aim of a stabilised final approach is to put the aircraft in a steady state condition, and your Vref is a fixed proportion above your Vs for the landing config and weight. You are still airborne and your flight condition is based on your progress through the air, not the ground. The only adjustment you should make for groundspeed is to adjust your vertical speed, your descent rate, to maintain the glidepath.