Given a number N, the task is to find the sum of first N Centered tridecagonal number.
A Centered tridecagonal number represents a dot at the center and other dots surrounding the center dot in the successive tridecagonal(13 sided polygon) layer. The first few Centered tridecagonal numbers are 1, 14, 40, 79 …
Examples:
Input: N = 3
Output: 55
Explanation:
1, 14 and 40 are the first three Centered tridecagonal number.
1 + 14 + 40 = 55.Input: N = 5
Output: 265
Approach:
- Initially, we need to create a function which will help us to calculate the NthCentered tridecagonal number.
- Now, Run a loop starting from 1 to N, and find the Centered tridecagonal numbers in this range.
- Add all the above calculated Centered tridecagonal numbers.
- Finally, display the sum of the first N Centered tridecagonal numbers.
Below is the implementation of the above approach:
// C++ program to find the sum of // the first Nth centered // tridecagonal number #include<bits/stdc++.h> using namespace std;
// Function to calculate the // N-th centered tridecagonal // number int Centered_tridecagonal_num( int n)
{ // Formula to calculate
// Nth centered tridecagonal
// number & return it
return (13 * n * (n - 1) + 2) / 2;
} // Function to find the sum // of the first N centered // tridecagonal numbers int sum_Centered_tridecagonal_num( int n)
{ // Variable to store
// the sum
int summ = 0;
// Loop to iterate and find the
// sum of first N centered
// tridecagonal numbers
for ( int i = 1; i <= n; i++)
{
summ += Centered_tridecagonal_num(i);
}
return summ ;
} // Driver code int main()
{ int n = 5;
cout << sum_Centered_tridecagonal_num(n)
<< endl;
return 0;
} // This code is contributed by rutvik_56 |
// Java program to find the sum of // the first Nth centered // tridecagonal number class GFG{
// Function to calculate the // N-th centered tridecagonal // number public static int Centered_tridecagonal_num( int n)
{ // Formula to calculate
// Nth centered tridecagonal
// number & return it
return ( 13 * n * (n - 1 ) + 2 ) / 2 ;
} // Function to find the sum // of the first N centered // tridecagonal numbers public static int sum_Centered_tridecagonal_num( int n)
{ // Variable to store
// the sum
int summ = 0 ;
// Loop to iterate and find the
// sum of first N centered
// tridecagonal numbers
for ( int i = 1 ; i <= n; i++)
{
summ += Centered_tridecagonal_num(i);
}
return summ ;
} // Driver code public static void main(String[] args)
{ int n = 5 ;
System.out.println(sum_Centered_tridecagonal_num(n));
} } // This code is contributed by divyeshrabadiya07 |
# Program to find the sum of # the first Nth # Centered_tridecagonal number # Function to calculate the # N-th Centered tridecagonal # number def Centered_tridecagonal_num(n):
# Formula to calculate
# Nth Centered tridecagonal
# number & return it
return ( 13 * n *
(n - 1 ) + 2 ) / / 2
# Function to find the sum # of the first N # Centered tridecagonal # numbers def sum_Centered_tridecagonal_num(n) :
# Variable to store
# the sum
summ = 0
# Loop to iterate and find the
# sum of first N Centered
# tridecagonal numbers
for i in range ( 1 , n + 1 ):
summ + = Centered_tridecagonal_num(i)
return summ
# Driver Code if __name__ = = '__main__' :
n = 5
print (sum_Centered_tridecagonal_num(n))
|
// C# program to find the sum of // the first Nth centered // tridecagonal number using System;
class GFG{
// Function to calculate the // N-th centered tridecagonal // number public static int Centered_tridecagonal_num( int n)
{ // Formula to calculate
// Nth centered tridecagonal
// number & return it
return (13 * n * (n - 1) + 2) / 2;
} // Function to find the sum // of the first N centered // tridecagonal numbers public static int sum_Centered_tridecagonal_num( int n)
{ // Variable to store
// the sum
int summ = 0;
// Loop to iterate and find the
// sum of first N centered
// tridecagonal numbers
for ( int i = 1; i <= n; i++)
{
summ += Centered_tridecagonal_num(i);
}
return summ;
} // Driver code public static void Main()
{ int n = 5;
Console.WriteLine(sum_Centered_tridecagonal_num(n));
} } // This code is contributed by Code_Mech |
<script> // Javascript program to find the sum of
// the first Nth centered
// tridecagonal number
// Function to calculate the
// N-th centered tridecagonal
// number
function Centered_tridecagonal_num(n)
{
// Formula to calculate
// Nth centered tridecagonal
// number & return it
return (13 * n * (n - 1) + 2) / 2;
}
// Function to find the sum
// of the first N centered
// tridecagonal numbers
function sum_Centered_tridecagonal_num(n)
{
// Variable to store
// the sum
let summ = 0;
// Loop to iterate and find the
// sum of first N centered
// tridecagonal numbers
for (let i = 1; i <= n; i++)
{
summ += Centered_tridecagonal_num(i);
}
return summ ;
}
let n = 5;
document.write(sum_Centered_tridecagonal_num(n));
// This code is contributed by divyesh072019.
</script> |
265
Time complexity: O(N).
Auxiliary Space: O(1) as it is using constant space for variables