#nullable enable

#region
var (_input, _iter) = (Array.Empty<string>(), 0);
T I<T>() where T : IParsable<T>
{
    while (_iter >= _input.Length) (_input, _iter) = (Console.ReadLine()!.Split(' '), 0);
    return T.Parse(_input[_iter++], null);
}
#endregion

static T[] Range<T>(int n, Func<T> F) => Enumerable.Range(0, n).Select(_ => F()).ToArray();

var n = I<int>();
var a = I<int>();
var b = I<int>();
var kz = Range(n + 1, I<long>);

Int128 fac = 1;
for (var i = 2; i <= n + 1; i++) fac *= i;

(Int128, Int128) F(int x)
{
    Int128 res = 0;
    Int128 xp = 1;
    for (var i = 0; i <= n; i++)
    {
        xp *= x;
        res += fac / (i + 1) * kz[i] * xp;
    }
    var (p, q) = Int128.DivRem(res, fac);
    if (q < 0) (p, q) = (p - 1, q + fac);
    return (p, q);
}

var (fap, faq) = F(a);
var (fbp, fbq) = F(b);
var ans = fbp - fap;
if (fbq < faq) ans--;
Console.WriteLine(ans);