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    "# Padovan sequence\n",
    "\n",
    "The Padovan sequence is the following infinite sequence of natural numbers:\n",
    "`1 1 1 2 2 3 4 5 7 9 12 16 21 28 37 ...`\n",
    "\n",
    "The sequence begins with the subsquence $[1, 1, 1]$ and then each term is the sum of two terms before the last one, that is:\n",
    "\n",
    "$P(0) = 1$\n",
    "\n",
    "$P(1) = 1$\n",
    "\n",
    "$P(2) = 1$\n",
    "\n",
    "$P(n) = P(n-2) + P(n-3)$\n",
    "\n",
    "The Padovan sequence is a cousin of the Fibonacci sequence and has many applications in applied mathematics. As a curiosity, the Padovan sequence can be represented as a set of joined equilateral triangles forming an spiral:\n",
    "\n",
    "<a title=\"The original uploader was Gandalf61 at English Wikipedia., CC BY-SA 3.0 &lt;http://creativecommons.org/licenses/by-sa/3.0/&gt;, via Wikimedia Commons\" href=\"https://commons.wikimedia.org/wiki/File:Padovan_triangles_(1).png\"><img width=\"512\" alt=\"Padovan triangles (1)\" src=\"https://upload.wikimedia.org/wikipedia/commons/c/cd/Padovan_triangles_%281%29.png\"></a>\n",
    "\n",
    "Recall that in Python, the last elements of the array can be accessed directly using negative indices, for example, `array[-1]` would be the last element of the array, `array [-2]` the second to last, and so on. Also, remember that the `append()` function, adds an element to the end of the array.\n",
    "\n",
    "With everything explained so far, **develop the following program**:\n",
    "\n",
    "A program that asks the user for a length and generates a Padovan sequence of that length, stores it in an array and prints the array. "
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