I think that is rather die deterioration instead of doubling. Basically, the die gets worn and old, and so it makes it look like it is doubled, but it isn't.
ive never seen it that strong, or have this particular look. plus, its the only letter that has any type of doubling. everything else looks clean. confusing it is :-(
Looks like a physical force on the top of the one, pushing it to the side. Maybe from a coin counter finger ( old type), or loose in a change pocket with other coins. Nickel metal coins are much harder than copper. No added value. IMO, Jim