import std.stdio;
import std.algorithm;
import std.string;
import std.conv;
import std.range;

void main()
{
    enum MAX_N = 10 ^^ 5, MAX_X = 10 ^^ 6 + 1;
    int[MAX_N] buf;
    immutable n = readln.chomp.to!int;
    readln.splitter.map!(to!int).copy(buf[]);
    auto set = buf[0..n].sort();
    int[int] cache;
    foreach_reverse (x; set) {
        cache[x] = iota(2 * x, MAX_X, x)
                    .filter!(i => set.contains(i))
                    .map!(i => cache[i])
                    .fold!max(0) + 1;
    }
    writeln(cache.values.fold!max);
}