021-amicable-numbers.ipynb

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    "# Amicable numbers\n",
    "## Problem 21 \n",
    "\n",
    "<div class=\"problem_content\" role=\"problem\">\n",
    "<p>Let d(<i>n</i>) be defined as the sum of proper divisors of <i>n</i> (numbers less than <i>n</i> which divide evenly into <i>n</i>).<br/>\n",
    "If d(<i>a</i>) = <i>b</i> and d(<i>b</i>) = <i>a</i>, where <i>a</i> &#8800; <i>b</i>, then <i>a</i> and <i>b</i> are an amicable pair and each of <i>a</i> and <i>b</i> are called amicable numbers.</p>\n",
    "<p>For example, the proper divisors of 220 are 1, 2, 4, 5, 10, 11, 20, 22, 44, 55 and 110; therefore d(220) = 284. The proper divisors of 284 are 1, 2, 4, 71 and 142; so d(284) = 220.</p>\n",
    "<p>Evaluate the sum of all the amicable numbers under 10000.</p>\n",
    "</div>"
   ]
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   "source": [
    "def solve():\n",
    "    # Your code here\n",
    "    \n"
   ]
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   "source": [
    "## Solution"
   ]
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   "cell_type": "code",
   "execution_count": null,
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   "outputs": [],
   "source": [
    "solve()"
   ]
  }
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