import std.c.stdio: printf;

template Binary(int depth, int a, alias B) {
    static if (depth == 0) {
        enum Binary = 1;
    } else {
        enum Binary = 1 + B!(depth - 1, 0, B) + B!(depth - 1, 1, B);
    }
}

void main() {
    enum int N = 550;
    enum int instantiations = Binary!(N, 0, Binary);
    printf("%d\n", instantiations);
}