How many triangles are in a deck of 52 playing cards?

A deck can be divided into 3 piles with different numbers in each pile in 225 ways. This answer does not consider which cards are in which pile - only the number of cards in each pile.

A deck can be divided into 3 piles with different numbers in each pile in 225 ways. This answer does not consider which cards are in which pile - only the number of cards in each pile.

A deck can be divided into 3 piles with different numbers in each pile in 225 ways. This answer does not consider which cards are in which pile - only the number of cards in each pile.

A deck can be divided into 3 piles with different numbers in each pile in 225 ways. This answer does not consider which cards are in which pile - only the number of cards in each pile.