Project Euler Q7 - LO Man Hei

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    "### Q7\n",
    "What is the 10001-st prime number?"
   ]
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    "def prime_numbers(n,max_len=False):\n",
    "    result = []\n",
    "    if max_len:\n",
    "        n = max_len**2//5000 + max_len*20\n",
    "    sieve = [True] * (n+1)\n",
    "    for p in range(2, n+1):\n",
    "        if (sieve[p]):\n",
    "            result.append(p)\n",
    "            if max_len and len(result) >= max_len:\n",
    "                return result\n",
    "            for i in range(p, n+1, p):\n",
    "                sieve[i] = False\n",
    "    return result\n",
    "\n",
    "def n_prime(n):\n",
    "    return prime_numbers(0,n)[-1]"
   ]
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      "CPU times: user 97.8 ms, sys: 77.7 ms, total: 175 ms\n",
      "Wall time: 175 ms\n"
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   "source": [
    "%%time\n",
    "n_prime(10001)"
   ]
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