Project Euler Q47 - LO Man Hei

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    "### Q47\n",
    "Find the first four consecutive integers to have four distinct prime factors. What is the first of these numbers?"
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    "def prime_factors(n):\n",
    "    i = 2\n",
    "    factors = set()\n",
    "    while i * i <= n:\n",
    "        if n % i:\n",
    "            i += 1\n",
    "        else:\n",
    "            n //= i\n",
    "            factors.add(i)\n",
    "    if n > 1:\n",
    "        factors.add(n)\n",
    "    return factors\n",
    "\n",
    "def distinct_prime_factors(n):\n",
    "    if n == 1:\n",
    "        return 2\n",
    "    i = 2\n",
    "    while True:\n",
    "        for j in range(n)[::-1]:\n",
    "            if len(prime_factors(i+j)) != n:\n",
    "                i += 1+j\n",
    "                break\n",
    "        else:\n",
    "            return i"
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    "%%time\n",
    "distinct_prime_factors(4)"
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