Random Medicare Card Generator

medicare_card.js

//Reference: http://www.clearwater.com.au/code/provider

const randomMedicareNumber = ()=>{
    let sum = Math.floor(Math.random() * 5) +2;
    const weights = [1, 3, 7, 9, 1, 3, 7, 9];
    let num = [sum]
    for(let i = 0 ; i < 7 ; i++){
        let n = Math.floor(Math.random()*10)
        sum += n * weights[i+1];
        num.push(n)
    }
    num.push(sum % 10)
    return num.join('') + '1/1';
}