Step 1:

The sum of the first odd natural numbers is a square number.

Draw the diagram for the first three square numbers.

First odd numbers are .

In the diagram blue colour dot represent and pink colour dot represent and green colour dot represent .

Observe the diagram:

Sum of  .

.

.

Step 2:

The sum of the first odd natural numbers is a square number.

Need to prove .

Odd natural numbers are .

	Sum of the first odd natural numbers
		\ \
		\ \
\ \
\ \
\ \

.