Icositrigonal Number | C ++ program to find nth Icositrigonal number ; Function to find N - th Icositrigonal number ; Formula to calculate nth Icositrigonal number ; Driver Code
#include <bits/stdc++.h> NEW_LINE using namespace std ; int Icositrigonal_num ( int n ) { return ( 21 * n * n - 19 * n ) / 2 ; } int main ( ) { int n = 3 ; cout << Icositrigonal_num ( n ) << endl ; n = 10 ; cout << Icositrigonal_num ( n ) ; return 0 ; }