Squares: 1-digit, 2-digit, 3-digit numbers

1^2 = 1

2^2 = 4

3^2 = 9

4^2 = 16

5^2 = 25

6^2 = 36

7^2 = 49

8^2 = 64

9^2 = 81

10^2 = 100 ..... 21^2 = 441
11^2 = 121 ..... 22^2 = 484

12^2 = 144 ..... 23^2 = 529

13^2 = 169 ..... 24^2 = 576

14^2 = 196 ..... 25^2 = 625

15^2 = 225 ..... 26^2 = 676

16^2 = 256 ..... 27^2 = 729

17^2 = 289 ..... 28^2 = 784

18^2 = 324 ..... 29^2 = 841

19^2 = 361 ..... 30^2 = 900

20^2 = 400 ..... 31^2 = 961