# Icosikaiheptagonal Number

• Last Updated : 23 Jun, 2021

Given a number N, the task is to find Nth icosikaiheptagonal number.

An icosikaiheptagonal number is a class of figurate numbers. It has 27 – sided polygon called icosikaiheptagon. The N-th icosikaiheptagonal number count’s the 27 number of dots and all other dots are surrounding with a common sharing corner and make a pattern. The first few icosikaiheptagonol numbers are 1, 27, 78, 154 …

Examples:

Input: N = 2
Output: 27
Explanation:
The second icosikaiheptagonol number is 27.
Input: N = 3
Output: 78

Approach: The N-th icosikaiheptagonal number is given by the formula:

• Nth term of s sided polygon = • Therefore Nth term of 27 sided polygon is •

Below is the implementation of the above approach:

## C++

 // C++ program to find N-th // icosikaiheptagonal number #include    using namespace std; // Function to find the nth // icosikaiheptagonal Number int icosikaiheptagonalNum(int n) {     return (25 * n * n - 23 * n) / 2; }   // Driver code int main() {     int n = 3;       cout << "3rd icosikaiheptagonal Number is "          << icosikaiheptagonalNum(n);       return 0; }

## Java

 // Java program to find N-th  // icosikaiheptagonal number  class GFG{    // Function to find the nth  // icosikaiheptagonal number  static int icosikaiheptagonalNum(int n)  {      return (25 * n * n - 23 * n) / 2;  }    // Driver code  public static void main(String[] args)  {      int n = 3;      System.out.print("3rd icosikaiheptagonal Number is " +                                  icosikaiheptagonalNum(n));  }  }    // This code is contributed by shubham

## Python3

 # Python3 program to find N-th # icosikaiheptagonal number   # Function to find the nth # icosikaiheptagonal Number def icosikaiheptagonalNum(n):       return (25 * n * n - 23 * n) // 2;   # Driver code n = 3; print("3rd icosikaiheptagonal Number is ",                  icosikaiheptagonalNum(n));   # This code is contributed by Code_Mech

## C#

 // C# program to find N-th  // icosikaiheptagonal number  using System;   class GFG{    // Function to find the nth  // icosikaiheptagonal number  static int icosikaiheptagonal(int n)  {      return (25 * n * n - 23 * n) / 2;  }    // Driver code  public static void Main(String[] args) {     int n = 3;            Console.Write("3rd icosikaiheptagonal Number is " +                                  icosikaiheptagonal(n));  }  }    // This code is contributed by shivanisinghss2110

## Javascript

 

Output:

3rd icosikaiheptagonal Number is 78

Time Complexity: O(1)

Auxiliary Space: O(1)

Reference: http://www.2dcurves.com/line/linep.html

My Personal Notes arrow_drop_up
Recommended Articles
Page :