给定数字n ,任务是找到第n个中心七边形数字。
居中的七边形数字是居中的图形编号,它代表一个以点为中心的七边形,而所有其他点都以七边形的形式包围。可以使用公式(7n 2 – 7n + 2)/ 2计算第N个中心的七边形数。
例子 :
Input : n = 2
Output : 8
Input : n = 7
Output : 148
请参考该图的图形表示。
下面是实现:
C++
// CPP program to find n-th
// Centered heptagonal number
#include
using namespace std;
// Function to find Centered
// heptagonal number
int centered_heptagonal_num(long int n)
{
// Formula to calculate nth
// Centered heptagonal number
return (7 * n * n - 7 * n + 2) / 2;
}
// Driver Code
int main()
{
long int n = 5;
cout << n << "th Centered heptagonal number : ";
cout << centered_heptagonal_num(n);
return 0;
}
Java
// Java program to find n-th Centered
// heptagonal number
import java.io.*;
class GFG {
// Function to find Centered heptagonal
// number
static long centered_heptagonal_num(long n)
{
// Formula to calculate nth
// Centered heptagonal number
return (7 * n * n - 7 * n + 2) / 2;
}
// Driver Code
public static void main (String[] args)
{
long n = 5;
System.out.println( n + "th Centered "
+ "heptagonal number : "
+ centered_heptagonal_num(n));
}
}
// This code is contributed by anuj_67.
Python3
# Python program to find nth
# Centered heptagonal number
# Function to find Centered
# heptagonal number
def centered_heptagonal_num(n):
# Formula to calculate nth
# Centered heptagonal number
return (7 * n * n - 7 * n + 2) // 2
# Driver Code
n = 5
print("%sth Centered heptagonal number : " %n,
centered_heptagonal_num(n))
C#
//C# program to find n-th Centered
// heptagonal number
using System;
class GFG {
// Function to find Centered heptagonal
// number
static long centered_heptagonal_num(long n)
{
// Formula to calculate nth
// Centered heptagonal number
return (7 * n * n - 7 * n + 2) / 2;
}
// Driver Code
public static void Main ()
{
long n = 5;
Console.WriteLine( n + "th Centered "
+ "heptagonal number : "
+ centered_heptagonal_num(n));
}
}
// This code is contributed by anuj_67.
PHP
Javascript
输出 :
5th Centered heptagonal number : 71