AMO · 2027 · Grades 6-7 · Self-study SET 29 Question 14

Stacy has 53 marbles and puts them into three nonempty piles, each containing an odd number of marbles. How many different ways can she do this? The order of the piles does not matter: 1, 1, 51 is the same arrangement as 1, 51, 1.

**Input:** Enter the integer only, without units.