For example, ‘2+4+6+8+10’ is a number series – the sum of the first five even numbers or the multiples of 2.

Most of the competitive exams or management aptitude tests frequently asked questions based on number series. In Number Series the examine would be given a particular sequence in which he’s to analyze the pattern followed by the said series and accordingly he would be asked to foretell the following number of the series following the same trend or pattern.

Types of Number Series Problems –

Add up Series (+) : Just adding a constant number everytime. For example: (13, 18, 23, 28 ….).

Add up Series (- ): , Just subtracting a constant number every time. For example : (28, 23, 18, 13 ……).

Step up Series (+/-) : Adding/Subtracting a variable number, in this case we are adding 2n for n = 0, 1, 2, 3 …… For example : 0, 2, 6, 12, 20…. or 20, 12, 6, 2, 0, 0 …..

Square up (+/-) – Given series is in the square of n where n= 1,2,3,4,5,6… i.e. 1,4,9,16,25,36…

Square add up Series(+/-) : Adding n^{2} every time and incrementing value of n starting from 1 i.e. 1,5, 14, 30, 55, …… and Subtracting n^{2} every time and decrementing value of n i.e. 34, 33, 29, 20,

Cube Up Series : Given series is in the cube of n where n = 1,2,3,4,5,6… i.e. 1,8,27,64,125,216….

Cube add up Series : Adding n^{3} every time with incrementing of n by 1 i.e. 1,9,36…

Prime up(+/-) : Sequence consist of Prime numbers i.e. 2,3,5,7,11…

Prime Square up(+/-) : Sequence consist of squares of prime numbers i.e. 4,9,25,49,121..

Arithmetic Series: Sequence consist of Arithmetic Progression i.e. 3,6,9,…

Geometric Series : Sequence consist of Geometric Progression i.e. 2,6,18,54,…