Number Series Questions

The given number series follows a pattern that, 4, 15, 37, 81, ?

4

4 + 11 = 15

15 + 22 = 37

37 + 44 = 81

81 + 88 = 169

Hence, the next number in the sequence is 169.

Here the series of the form is x2 - 1, x2 - 2, x2 - 3,...

 53 x 2 - 4 = 106 - 4 = 102

The given number series is 8, 14, 24, 40, ? .

It follows a pattern that,

8

8 x 1.5 + 2 = 14

14 x 1.5 + 3 = 24

24 x 1.5 + 4 = 40

40 x 1.5 + 5 = 65

Hence, the next number in the given number series is 65.

Here 2nd number = (1st number x 1 )+1

 3rd number = (2nd number x 2 +2) 

4th number = (3rd number x 3 )+3 and so on..

Therefore, 5th number = (4th number x 4) +4 =57 x 4 + 4 =232.

$$\begin{gathered} 63+6=222 \\ \end{gathered}$$ 

Similarly , 253+25=15650

Two series alternate here, with every third number following a different pattern.
In the main series, 4 is added to each number to arrive the next.
In alternate series, 5 is subtracted from each number t arrive the next number.
Here in the main series
3 + 4 = 7
7 + 4 = 11
11 + 4 = 15
15 + 4 = 19

In alternate series
24 - 5 = 19
19 - 5 = 14...

The given sequence is a combination of three series:
i)1st, 4th, 7th terms i.e, 2, 4, 9
ii)2nd, 5th, 8th terms i.e, 3, 6, 12
iii)3rd, 6th, 9th terms i.e, 4, 8, 16
In each one of i, ii, iii, each term is twice the preceding term.
So, 9 is wrong and must be replaced by (4*2) = 8