1. Triangular 5.1 Basic Series (1/3) A series forms a pattern
Common Series:
Triangular 1 3 6 10 15 21 28 36 45 1 +2 +3 +4 +5 +6 +7 +8 +9

2. Square 5.1 Basic Series (2/3) A series forms a pattern Common Series:
Demo
Common Series:
Square 1 4 9 16 25 36 1 +3 +5 +7 +9
+11

3. Each term is found by adding previous 2 terms.
5.1 Basic Series (3/3)
A series forms a pattern
Video
Common Series:
Fibonacci
Start with One.
Each term is found by adding previous 2 terms. 1 1 2 3 5 8 13 21 34 55 + 1 1 + 1 + 2 2 + 3 3 + 5 5 + 8 8 + 13 13 + 21 21 + 34