097-large-non-mersenne-prime.ipynb

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    "# Large non-Mersenne prime\n",
    "## Problem 97 \n",
    "\n",
    "<div class=\"problem_content\" role=\"problem\">\n",
    "<p>The first known prime found to exceed one million digits was discovered in 1999, and is a Mersenne prime of the form 2<sup>6972593</sup>&#8722;1; it contains exactly 2,098,960 digits. Subsequently other Mersenne primes, of the form 2<sup><i>p</i></sup>&#8722;1, have been found which contain more digits.</p>\n",
    "<p>However, in 2004 there was found a massive non-Mersenne prime which contains 2,357,207 digits: 28433&#215;2<sup>7830457</sup>+1.</p>\n",
    "<p>Find the last ten digits of this prime number.</p>\n",
    "</div>"
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    "def solve():\n",
    "    base = 10**10\n",
    "    tail = pow(2, 7830457, base)\n",
    "    tail *= 28433\n",
    "    tail += 1\n",
    "    return int(tail % base)"
   ]
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   "source": [
    "## Solution"
   ]
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      "text/plain": [
       "8739992577"
      ]
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     "execution_count": 2,
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   "source": [
    "solve()"
   ]
  }
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