{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "Fn_1 = 1\n",
    "Fn = 1\n",
    "n = 2\n",
    "\n",
    "while Fn < 10**999:\n",
    "    Fn_1, Fn = Fn,  Fn_1 + Fn\n",
    "    n += 1"
   ]
  }
 ],
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  "kernelspec": {
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   "language": "python",
   "name": "python3"
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  "title": "1000-digit Fibonacci number"
 },
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