fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: usize = n.trim().parse().unwrap();
    let mut a = String::new();
    std::io::stdin().read_line(&mut a).ok();
    let a: Vec<usize> = a.trim().split_whitespace().map(|s| s.parse().unwrap()).collect();

    let mut mapping = vec![0usize; 3];
    for i in 0..n {
        let idx = (a[i]-1).min(2);
        mapping[idx] += 1;
    }
    let mut result = 0usize;
    if mapping[0] > 1 {
        result += mapping[0] * (mapping[0]-1) / 2 * 2;
    }
    result += mapping[0] * mapping[1] * 3;
    result += mapping[0] * mapping[2] * 2;
    if mapping[1] > 1 {
        result += mapping[1] * (mapping[1]-1) / 2 * 1;
    }
    result += mapping[1] * mapping[2] * 1;
    if mapping[2] > 1 {
        result += mapping[2] * (mapping[2]-1) / 2 * 1;
    }
    println!("{}", result);
}