mersenneprimenumberlist

mersenneprimenumberlist.go

package main

import (
	"fmt"
	"math"
)

//  Golang program for
//  Display mersenne prime numbers from 1 to n

func IsPrime(num int64) int64 {
	/**
	if num < 2 {
		fmt.Println("Number must be greater than 2.")
		return
	} **/
	var sq_root int64
	sq_root = int64(math.Sqrt(float64(num)))
	var i int64
	for i = 2; i <= sq_root; i++ {
		if num%i == 0 {
			//fmt.Println("false")

		}
	}
	return num
}

// Print the Mersenne prime number
func listOfMersenneNo(n int64) {
	// How to check if a number is a mersenne prime
	// Condition number greater than 1 And
	// Number is prime And
	// When a number is divided by 2 it's never an
	// even number till the number is zero.

	var p int64
	var num int64
	for p = 2; p <= n; p++ {
		num = (1 << p) - 1

		if IsPrime(num) == num {
			fmt.Println(num)
		}

	}
}

func main() {
	var i int64
	fmt.Scan(&i)
	listOfMersenneNo(i)
}