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<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>Hollow Square of 1s</title>
</head>
<body>
  <pre id="out"></pre>
  <script>
    const n = 5;
    let result = "";

    for (let i = 1; i <= n; i++) {
      let line = "";
      for (let j = 1; j <= n; j++) {
        if (i === 1 || i === n || j === 1 || j === n) {
          line += "1 ";
        } else {
          line += "  ";
        }
      }
      result += line + "\n";
    }

    document.getElementById("out").textContent = result;
  </script>
</body>
</html>

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