Number of Distinct Roll Sequences LeetCode solution in JavaScript

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var distinctSequences = function (n) {
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  // 3D DP [n + 1][7][7] => rollIdx, prev, prevPrev
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  const dp = Array.from({ length: n + 1 }, () => {
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    return new Array(7).fill(0).map(() => new Array(7).fill(0));
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  });
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  const gcd = (a, b) => {
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    if (a < b) [b, a] = [a, b];
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    while (b) {
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      let temp = b;
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      b = a % b;
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      a = temp;
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    }
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    return a;
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  };
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  const ds = (n, p = 0, pp = 0) => {
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    if (n == 0) return 1;
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    if (dp[n][p][pp] == 0) {
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      for (let i = 1; i <= 6; i++) {
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        if (i != p && i != pp && (p == 0 || gcd(p, i) == 1)) {
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          dp[n][p][pp] = (dp[n][p][pp] + ds(n - 1, i, p)) % 1000000007;
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        }
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      }
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    }
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    return dp[n][p][pp];
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  };
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  return ds(n);
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};