Programa para encontrar el término N de la serie 1, 6, 17, 34, 56, 86, 121, 162, …….

Dado un número N. La tarea es escribir un programa para encontrar el N-ésimo término de la siguiente serie:
 

1, 6, 17, 34, 56, 86, 121, 162, …..(Términos N)

Ejemplos: 
 

Input: N = 4
Output: 34
For N = 4
4th Term = ( 3 * 4 * 4 - 4 * 4 + 2) 
         = 34

Input: N = 10
Output: 261

Enfoque: El enésimo término generalizado de esta serie: 
 

A continuación se muestra la implementación requerida: 
 

// C++ program to find the N-th term of the series:
// 1, 6, 17, 34, 56, 86, 121, 162, .....
#include <iostream>
#include <math.h>
using namespace std;
 
// calculate Nth term of series
int nthTerm(int n)
{
    return 3 * pow(n, 2) - 4 * n + 2;
}
 
// Driver code
int main()
{
    int N = 4;
 
    cout << nthTerm(N) << endl;
 
    return 0;
}

// Java program to find the N-th term of the series:
// 1, 6, 17, 34, 56, 86, 121, 162, .....
 
public class GFG {
     
    // calculate Nth term of series
    static int nthTerm(int n)
    {
        return 3 * (int) Math.pow(n, 2) - 4 * n + 2;
    }
       
    // Driver code
    public static void main(String args[])
    {
        int N = 4;
           
       System.out.println(nthTerm(N));
     
    }
    // This Code is contributed by ANKITRAI1
}

# Python program to find the
# N-th term of the series:
# 1, 6, 17, 34, 56, 86, 121, 162, .....
 
# calculate Nth term of series
def nthTerm(n):
 
    return 3 * pow(n, 2) - 4 * n + 2
 
# Driver code
N = 4
print(nthTerm(N))
 
# This code is contributed by
# Sanjit_Prasad

// C# program to find the
// N-th term of the series:
// 1, 6, 17, 34, 56, 86, 121, 162, .....
using System;
class GFG
{
     
// calculate Nth term of series
static int nthTerm(int n)
{
    return 3 * (int) Math.Pow(n, 2) -
                         4 * n + 2;
}
     
// Driver code
public static void Main()
{
    int N = 4;
         
    Console.Write(nthTerm(N));
}
}
 
// This code is contributed
// by ChitraNayal

<?php
// PHP program to find the
// N-th term of the series:
// 1, 6, 17, 34, 56, 86, 121, 162, .....
 
// calculate Nth term of series
function nthTerm($n)
{
    return 3 * pow($n, 2) -
           4 * $n + 2;
}
 
// Driver code
$N = 4;
 
echo nthTerm($N)."\n";
 
// This code is contributed
// by ChitraNayal
?>

<script>
// JavaScript program to find the N-th term of the series:
// 1, 6, 17, 34, 56, 86, 121, 162, .....
 
// calculate Nth term of series
function nthTerm(n)
{
    return 3 * Math.pow(n, 2) - 4 * n + 2;
}
 
// Driver code
let N = 4;
 
     document.write( nthTerm(N) );
 
// This code contributed by gauravrajput1
 
</script>

34

Complejidad de tiempo: O(1)

Complejidad espacial : O (1) ya que usa variables constantes