euler/ipython/EulerProblem006.ipynb

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   "source": [
    "# Euler Problem 6\n",
    "\n",
    "The sum of the squares of the first ten natural numbers is,\n",
    "\n",
    "$1^2 + 2^2 + ... + 10^2 = 385$\n",
    "\n",
    "The square of the sum of the first ten natural numbers is,\n",
    "\n",
    "$(1 + 2 + ... + 10)^2 = 55^2 = 3025$\n",
    "\n",
    "Hence the difference between the sum of the squares of the first ten natural numbers and the square of the sum is $3025 − 385 = 2640$.\n",
    "\n",
    "Find the difference between the sum of the squares of the first one hundred natural numbers and the square of the sum."
   ]
  },
  {
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   "source": [
    "Okay, this is as straightforward as it can get."
   ]
  },
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     "text": [
      "25164150\n"
     ]
    }
   ],
   "source": [
    "s = sum([x for x in range(1, 101)])**2  - sum([x**2 for x in range(1, 101)])\n",
    "assert(s == 25164150)\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "General solution."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "def diff_between_sum_of_squares_and_square_sum(n):\n",
    "    return sum([x for x in range(1, n + 1)])**2  - sum([x**2 for x in range(1, n + 1)])\n",
    "\n",
    "assert(diff_between_sum_of_squares_and_square_sum(100) == 25164150)\n",
    "assert(diff_between_sum_of_squares_and_square_sum(10) == 2640)"
   ]
  }
 ],
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