Given a number N. The task is to write a program to find the Nth term in the below series:
1, 1, 2, 6, 24…
Examples:
Input: 3 Output: 2 For N = 3 Nth term = (N-1)! = 2 Input: 5 Output: 24
Nth term of the series is given by below formula:
Nth term = ( N-1)!
Below is the required implementation:
C++
// CPP program to find N-th term of the series: // 1, 1, 2, 6, 24... #include <iostream> using namespace std;
// calculate Nth term of series int nthTerm( int N)
{ if (N <= 1)
return 1;
int i, fact = 1;
for (i = 1; i < N; i++)
fact = fact * i;
return fact;
} // Driver Function int main()
{ int N = 3;
cout << nthTerm(N);
return 0;
} |
Java
// Java program to find the Nth term import java.io.*;
// calculate Nth term of this series // 1, 1, 2, 6, 24... class Nth {
public int nthTerm( int N)
{
// By using above formula
if (N <= 1 )
return 1 ;
int i, fact = 1 ;
for (i = 1 ; i < N; i++)
fact = fact * i;
return fact;
}
} // Main class for main method class GFG {
public static void main(String[] args)
{
int N = 3 ;
// create object of Class Nth
Nth a = new Nth();
// call and print Nth term
System.out.println(a.nthTerm(N));
}
} |
Python 3
# Python 3 program to find # N-th term of the series: # 1, 1, 2, 6, 24... # Function to calculate # Nth term of series def nthTerm(n) :
if n < = 1 :
return 1
fact = 1
for i in range ( 1 , N) :
fact = fact * i
return fact
# Driver code if __name__ = = "__main__" :
N = 3
# function calling
print (nthTerm(N))
# This code is contributed # by ANKITRAI1 |
C#
// C# program to find the // Nth term of the series // 1, 1, 2, 6, 24... using System;
// calculate Nth term class GFG
{ public int nthTerm( int N)
{ // By using above formula
if (N <= 1)
return 1;
int i, fact = 1;
for (i = 1; i < N; i++)
fact = fact * i;
return fact;
} // Driver Code public static void Main()
{ int N = 3;
// create object of Class GFG
GFG a = new GFG();
// call and print Nth term
Console.Write(a.nthTerm(N));
} } // This code is contributed // by ChitraNayal |
PHP
<?php // PHP program to find N-th // term of the series: // 1, 1, 2, 6, 24... // calculate Nth term of series function nthTerm( $N )
{ if ( $N <= 1)
return 1;
$fact = 1;
for ( $i = 1; $i < $N ; $i ++)
$fact = $fact * $i ;
return $fact ;
} // Driver Code $N = 3;
echo nthTerm( $N );
// This code is contributed // by ChitraNayal ?> |
Javascript
<script> // JavaScript program to find N-th term of the series: // 1, 1, 2, 6, 24... // calculate Nth term of series function nthTerm( N)
{ if (N <= 1)
return 1;
let i, fact = 1;
for (i = 1; i < N; i++)
fact = fact * i;
return fact;
} // Driver Function let N = 3;
document.write(nthTerm(N));
// This code contributed by Rajput-Ji </script> |
Output:
2
Time Complexity: O(N), where N represents the given integer.
Auxiliary Space: O(1), no extra space is required, so it is a constant.