Project Euler Q55 - LO Man Hei

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   "source": [
    "### Q55\n",
    "How many Lychrel numbers are there below ten-thousand?"
   ]
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    "def is_palindrome(n):\n",
    "    return str(n) == str(n)[::-1]\n",
    "\n",
    "def lychrel_numbers_under_n(n):\n",
    "    result = set()\n",
    "    for num in range(n,0,-1):\n",
    "        temp = num\n",
    "        for i in range(50):\n",
    "            temp += int(str(temp)[::-1])\n",
    "            if is_palindrome(temp):\n",
    "                break\n",
    "            if temp in result:\n",
    "                result.add(num)\n",
    "                break\n",
    "        else:\n",
    "            result.add(num)\n",
    "    return result"
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     "text": [
      "CPU times: user 19.1 ms, sys: 0 ns, total: 19.1 ms\n",
      "Wall time: 17.5 ms\n"
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       "249"
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   "source": [
    "%%time\n",
    "len(lychrel_numbers_under_n(10000))"
   ]
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   "source": []
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