MathDB
Ms. Math's Playing Blocks

Source: 2013 AIME I Problem 11

March 15, 2013
modular arithmeticAIME

Problem Statement

Ms. Math's kindergarten class has 1616 registered students. The classroom has a very large number, NN, of play blocks which satisfies the conditions:
(a) If 1616, 1515, or 1414 students are present, then in each case all the blocks can be distributed in equal numbers to each student, and (b) There are three integers 0<x<y<z<140 < x < y < z < 14 such that when xx, yy, or zz students are present and the blocks are distributed in equal numbers to each student, there are exactly three blocks left over.
Find the sum of the distinct prime divisors of the least possible value of NN satisfying the above conditions.