for i=1 to n do {
    for j=1 to i do {
        print("Hello")
    }
}

i=1         i=2         i=3      ...   i=n
"Hello"     "Hello"     "Hello"        "Hello"
            "Hello"     "Hello"        "Hello"
                        "Hello"        "Hello"
                                       ...
                                       "Hello"