MathDB

1

Part of 1999 IberoAmerican

Problems(2)

14th ibmo - cuba 1999/q4.

Source: Spanish Communities

4/16/2006
Let BB be an integer greater than 10 such that everyone of its digits belongs to the set {1,3,7,9}\{1,3,7,9\}. Show that BB has a prime divisor greater than or equal to 11.
calculusintegrationinductionnumber theory unsolvednumber theory
14th ibmo - cuba 1999/q1.

Source: Spanish Communities

4/16/2006
Find all the positive integers less than 1000 such that the cube of the sum of its digits is equal to the square of such integer.
geometry3D geometrynumber theory unsolvednumber theory