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    "# Combinatoric selections (Euler Problem 53)"
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    "[https://projecteuler.net/problem=53](https://projecteuler.net/problem=53)\n",
    "\n",
    "There are exactly ten ways of selecting three from five, 12345:\n",
    "\n",
    "$123, 124, 125, 134, 135, 145, 234, 235, 245, 345$\n",
    "\n",
    "In combinatorics, we use the notation, 5C3 = 10.\n",
    "\n",
    "In general,\n",
    "\n",
    "$nCr = \\frac{n!}{r!(n−r)!}$, where r ≤ n, n! = n×(n−1)×...×3×2×1, and 0! = 1.\n",
    "\n",
    "It is not until n = 23, that a value exceeds one-million: 23C10 = 1144066.\n",
    "\n",
    "How many, not necessarily distinct, values of  nCr, for 1 ≤ n ≤ 100, are greater than one-million?"
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