function isPrime(n) {
    for (var i = 2; i < n; i++) {
        if (n % i === 0) {
            return false
        }
    }
    return n > 1
}

function createPrimes(n) {
    if (n < 2) {
        return []
    }
    var primes = [2]
    for (var next = 3; next <= n; next++) {
        if (isPrime(next)){
            primes.push(next)
        }
    }
    return primes
}

function expandSeries(array) {
    if (array[0] > array[1]) {
        var tmp = array[0]
        array[0] = array[1]
        array[1] = tmp
    }
    var limit = array.pop()
    var i = array[0] + 1
    while (i <= limit) {
        array.push(i)
        i++
    }
    return array
}

function mcm(a, b) {
    var primes = createPrimes(a > b ? a : b)
    var factors = []
    var i = 0
    while (i < primes.length) {
        if (a % primes[i] === 0 && b % primes[i] === 0) {
            factors.push(primes[i])
            a = a / primes[i]
            b = b / primes[i]
            continue
        }
        if (a % primes[i] === 0) {
            factors.push(primes[i])
            a = a / primes[i]
            continue
        }
        if (b % primes[i] === 0) {
            factors.push(primes[i])
            b = b / primes[i]
            continue
        }
        i++
    }
    return factors.reduce((acc, val) => {
        return acc * val
    })
}

function smallestCommons(array) {
    return expandSeries(array).reduce((acc, val) => {
        return mcm(acc, val)
    })
}