First, it's Alpine, second, it depends on your definition of "mountain"
I would say there are only 2 or 3, Mont Blanc, and Monte Rosa. Monte Rosa could be divided into Dufourspitze and the Nordend, leaving you with three alpine 15'ers. Weisshorn and Dom are just below the 15K mark (at around 14.8-14.9) Remember that 15,000 foot equals about 4570 meters, and not 4500 as most people think. There are 3.282 ft in one meter.
Cheers,
Clint.
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