Given a number
14, 28, 20, 40, 32, 64…..
Examples:
Input : N = 5 Output : 32 Input : N = 6 Output : 64
Approach:
- Initialize first number with 14.
- Run a loop from i = 2 to N and do following steps:
- For Even i, double the previous term. For example if i = 2, current term will be 2*(term when i = 1), that is 2*14 = 28.
- For Odd i, subtract 8 from the previous term.
- Exit the loop and print the final number.
Below is the implementation of the above approach:
C++
// CPP program to find the Nth term of // the series 14, 28, 20, 40, ….. #include <iostream> using namespace std;
// Function to find the N-th term int findNth( int N)
{ // initializing the 1st number
int b = 14;
int i;
// loop from 2nd term to nth term
for (i = 2; i <= N; i++) {
// if i is even, double the
// previous number
if (i % 2 == 0)
b = b * 2;
// if i is odd, subtract 8 from
// previous number
else
b = b - 8;
}
return b;
} // Driver Code int main()
{ int N = 6;
cout << findNth(N);
return 0;
} |
Java
// Java program to find the Nth term of // the series 14, 28, 20, 40, import java.io.*;
class GFG {
// Function to find the N-th term static int findNth( int N)
{ // initializing the 1st number
int b = 14 ;
int i;
// loop from 2nd term to nth term
for (i = 2 ; i <= N; i++) {
// if i is even, double the
// previous number
if (i % 2 == 0 )
b = b * 2 ;
// if i is odd, subtract 8 from
// previous number
else
b = b - 8 ;
}
return b;
} // Driver Code public static void main (String[] args) {
int N = 6 ;
System.out.print(findNth(N));
}
} // This code is contributed by shs |
Python 3
# Python 3 program to find the Nth term # of the series 14, 28, 20, 40, ….. # Function to find the N-th term def findNth(N):
# initializing the 1st number
b = 14
# loop from 2nd term to nth term
for i in range ( 2 , N + 1 ):
# if i is even, double the
# previous number
if (i % 2 = = 0 ):
b = b * 2
# if i is odd, subtract 8 from
# previous number
else :
b = b - 8
return b
# Driver Code N = 6
print (findNth(N))
# This code is contributed # by Akanksha Rai |
C#
// C# program to find the Nth term of // the series 14, 28, 20, 40, using System;
public class GFG{
// Function to find the N-th term
static int findNth( int N)
{ // initializing the 1st number
int b = 14;
int i;
// loop from 2nd term to nth term
for (i = 2; i <= N; i++) {
// if i is even, double the
// previous number
if (i % 2 == 0)
b = b * 2;
// if i is odd, subtract 8 from
// previous number
else
b = b - 8;
}
return b;
} // Driver Code static public void Main (){
int N = 6;
Console.WriteLine(findNth(N));
}
} // This code is contributed by ajit |
PHP
<?php // PHP program to find the Nth term of // the series 14, 28, 20, 40, ….. // Function to find the N-th term function findNth( $N )
{ // initializing the 1st number
$b = 14;
// loop from 2nd term to nth term
for ( $i = 2; $i <= $N ; $i ++)
{
// if i is even, double the
// previous number
if ( $i % 2 == 0)
$b = $b * 2;
// if i is odd, subtract 8 from
// previous number
else
$b = $b - 8;
}
return $b ;
} // Driver Code $N = 6;
echo findNth( $N );
// This code is contributed by akt_mit ?> |
Javascript
<script> // java script program to find the Nth term of // the series 14, 28, 20, 40, ….. // Function to find the N-th term function findNth(N)
{ // initializing the 1st number
let b = 14;
// loop from 2nd term to nth term
for (let i = 2; i <= N; i++)
{
// if i is even, double the
// previous number
if (i % 2 == 0)
b = b * 2;
// if i is odd, subtract 8 from
// previous number
else
b = b - 8;
}
return b;
} // Driver Code N = 6; document.write(findNth(N)); // This code is contributed // by pulamolu mohan pavan cse </script> |
Output:
64
Time Complexity: O(N)
Auxiliary Space: O(1)