Given a number N. The task is to write a program to find the Nth term in the below series:
1, 8, 54, 384...
Examples:
Input : 3 Output : 54 For N = 3 Nth term = ( 3*3) * 3! = 54 Input : 2 Output : 8
On observing carefully, the Nth term in the above series can be generalized as:
Nth term = ( N*N ) * ( N! )
Below is the implementation of the above approach:
C++
// CPP program to find N-th term of the series: // 1, 8, 54, 384... #include <iostream> using namespace std;
// calculate factorial of N int fact( int N)
{ int i, product = 1;
for (i = 1; i <= N; i++)
product = product * i;
return product;
} // calculate Nth term of series int nthTerm( int N)
{ return (N * N) * fact(N);
} // Driver Function int main()
{ int N = 4;
cout << nthTerm(N);
return 0;
} |
Java
// Java program to find N-th term of the series: // 1, 8, 54, 384... import java.io.*;
// Main class for main method class GFG {
public static int fact( int N)
{
int i, product = 1 ;
// Calculate factorial of N
for (i = 1 ; i <= N; i++)
product = product * i;
return product;
}
public static int nthTerm( int N)
{
// By using above formula
return (N * N) * fact(N);
}
public static void main(String[] args)
{
int N = 4 ; // 4th term is 384
System.out.println(nthTerm(N));
}
} |
Python 3
# Python 3 program to find # N-th term of the series: # 1, 8, 54, 384... # calculate factorial of N def fact(N):
product = 1
for i in range ( 1 , N + 1 ):
product = product * i
return product
# calculate Nth term of series def nthTerm(N):
return (N * N) * fact(N)
# Driver Code if __name__ = = "__main__" :
N = 4
print (nthTerm(N))
# This code is contributed # by ChitraNayal |
C#
// C# program to find N-th // term of the series: // 1, 8, 54, 384... using System;
class GFG
{ public static int fact( int N)
{ int i, product = 1;
// Calculate factorial of N
for (i = 1; i <= N; i++)
product = product * i;
return product;
} public static int nthTerm( int N)
{ // By using above formula
return (N * N) * fact(N);
} // Driver Code public static void Main(String[] args)
{ int N = 4; // 4th term is 384
Console.WriteLine(nthTerm(N));
} } // This code is contributed // by Kirti_Mangal |
PHP
<?php // PHP program to find N-th /// term of the series: // 1, 8, 54, 384... // calculate factorial of N function fact( $N )
{ $product = 1;
for ( $i = 1; $i <= $N ; $i ++)
$product = $product * $i ;
return $product ;
} // calculate Nth term of series function nthTerm( $N )
{ return ( $N * $N ) * fact( $N );
} // Driver Code $N = 4;
echo nthTerm( $N );
// This code is contributed // by ChitraNayal ?> |
Javascript
<script> // JavaScript program to find N-th term of the series: // 1, 8, 54, 384... // calculate factorial of N function fact( N)
{ let i, product = 1;
for (i = 1; i <= N; i++)
product = product * i;
return product;
} // calculate Nth term of series function nthTerm( N)
{ return (N * N) * fact(N);
} // Driver Function let N = 4;
document.write(nthTerm(N));
// This code contributed by Rajput-Ji </script> |
Output:
384
Time Complexity: O(N)
Space Complexity: O(1) because using constant variables