function redJohn(n) {
    const r = x => Math.round(x)
    const s = x => Math.sqrt(x)
    
    const fact = (n) => n <= 1 ? 1 : fact(n - 1) * n
    
    const prime = (n) => { 
        if (n % 2 == 0 && n > 2) 
            return false
        for (let i=3; i <= r(s(n)); i+=2)
            if (n % i == 0)
                return false
        return true
    }
    
    let M = 0
    for (let i=0; i <= n/4; i++) {
        M += r(fact(n-i*3) / (fact(i) * fact(n-i*4)))
    }
    let res = 0
    for (let i=2; i <= M; i++)
        if (prime(i))
            res++
    return res
}