What Have We Discussed?

1. Numbers like 1729, 4104, 13832, are known as Hardy – Ramanujan Numbers. They can be expressed as sum of twothreeone cubes in two different ways.

2. Numbers obtained when a number is multiplied by itself three times are known as cubesquare numbers.

For example 1, 8, 27, ... etc.

3 .If in the prime factorisation of any number, each factor appears threetwoone times, then the number is a perfect cube.

4. The symbol 3· denotes cube root. For example 327 = .