The above answers are the squares of 1, 2, 3, 4 and 5 respectively. The square number of 6 is 36, which is greater than 30, which does not meet the requirements of the topic, so the following number is not the answer.

The square number means that this number is the square of another integer, for example, 4 is the square of 2.

There are many squares, which can be listed one by one.

note:

1. To know the square number, you must first know the square. Square refers to the multiplication of two identical numbers, and the result of multiplication is square number;

2. Special: the square of 1 is itself;

3,0 is not a square number.

Extended data:

The smallest 30 complete squares are (OEIS series A000290):

1? = 1, 2? = 4 ,3? = 9, 4? = 16, 5? = 25, 6? = 36 ,7? = 49 ,8? = 64 ,9? = 8 1 , 10? = 100,

1 1? = 12 1, 12? = 144 , 13? = 169 , 14? = 196 , 15? = 225, 16? = 256, 17? = 289 , 18? = 324, 19? = 36 1 ,20? = 400,

2 1? = 44 1 ,22? = 484, 23? = 529 ,24? = 576, 25? = 625 ,26? = 676, 27? = 729 ,28? = 784 ,29? = 84 1, 30? = 900