A so-called “star number”, s, is a number defined by the formula: s = 6n(n-1) + 1 where n is the index of the star number. Thus the first six (i.e. for n = 1, 2, 3, 4, 5 and 6) star numbers are: 1, 13, 37, 73, 121, 181

In contrast a so-called “triangle number”, t, is the sum of the numbers from 1 to n: t = 1 + 2 + … + (n-1) + n. Thus the first six (i.e. for n = 1, 2, 3, 4, 5 and 6) triangle numbers are: 1, 3, 6, 10, 15, 21

Write a Java application that produces a list of all the values of type int that are both star number and triangle numbers.

Hey, I have some questions how to write this program, I have started it and there's what I have so far, what I want to ask is should I create an endless loop? I want to find star numbers first , then to find triangular numbers and just try if it works, then I thought of creating a function where both will be displayed. Am I on the right track?
Thanks)

``````import java.util.Scanner;

public class triangular_stars {

public static void main(String[] args) {

int stars = findStarNumber(0);
int triangular=findTriangularNumber(0);
}

public static int findStarNumber(int stars) {

int ending_number = 10;
for (int i= 1; i <ending_number; i++) {

int s=0;
for(int n=1; n>i; n++){
s= 6 * n * (n - 1) + 1;

}
System.out.println(i +" = " + s);

}
return ending_number;
}

public static int findTriangularNumber(int t){

int starting_number = 1;

int ending_number = 100;

for (int i = starting_number; i <= ending_number; i++) {

int triangular = 0;

for (int j = 1; j <= i; j++) {

triangular = triangular + j;

}
System.out.println(i + " = " + triangular);
}
return ending_number;
}
}
``````

I found issue in generating StarNumber in the function findStarNumber.
You just need to modify the code at line 14

``````14 for(int n=1; n>i; n++){ // ..should be .....> for(int n=-1; n<=i; n++){
``````

When i ran the program for number range 1 to 100 there is only one instance where "triangular number" is equal to "star-Number" which is 1.

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