Prime Triplets
A prime triplet is a set of three prime numbers of the form (p, p + 2, p + 6) or (p, p + 4, p + 6)
The first prime triplets are:
(5, 7, 11), (7, 11, 13), (11, 13, 17), (13, 17, 19), (17, 19, 23), (37, 41, 43), (41, 43, 47), (67, 71, 73), (97, 101, 103), (101, 103, 107), (103, 107, 109), (107, 109, 113), (191, 193, 197), (193, 197, 199), (223, 227, 229), (227, 229, 233), (277, 281, 283), (307, 311, 313), (311, 313, 317), (347, 349, 353), (457, 461, 463), (461, 463, 467), (613, 617, 619), (641, 643, 647), (821, 823, 827), (823, 827, 829), (853, 857, 859), (857, 859, 863), (877, 881, 883), (881, 883, 887)
import java.io.*;
public class prime_triplet
{
public boolean isprime(int n)
{
int i;
for(i=2;i<=n/2;i++)
{
if(n%i==0)
return false;
}
return true;
}
public void print(int s, int l)
{
int i, tmp;
if(s>=l)
{
tmp = s;
s = l;
l = tmp;
}
System.out.println("The prime triplets are:");
for(i=s;i<=l;i++)
{
if(isprime(i)&&isprime(i+2)&&isprime(i+6))
{
System.out.println(i+", "+(i+2)+", "+(i+6));
}
if(isprime(i)&&isprime(i+4)&&isprime(i+6))
{
System.out.println(i+", "+(i+4)+", "+(i+6));
}
}
}
public static void main()throws IOException
{
BufferedReader r = new BufferedReader(new InputStreamReader(System.in));
int x, y;
System.out.println("Enter the lower limit:");
x = Integer.parseInt(r.readLine());
System.out.println("Enter the upper limit:");
y = Integer.parseInt(r.readLine());
prime_triplet obj = new prime_triplet();
obj.print(x, y);
}
}