diff --git a/triangle.py b/triangle.py
new file mode 100644
index 0000000..f72fa4f
--- /dev/null
+++ b/triangle.py
@@ -0,0 +1,26 @@
+def pascals_triangle(num_rows):
+    """Build Pascal's triangle as a list of rows.
+
+    Each row is generated from the previous one, where every interior
+    value is the sum of the two values above it.
+    """
+    triangle = []
+    for i in range(num_rows):
+        row = [1] * (i + 1)
+        for j in range(1, i):
+            row[j] = triangle[i - 1][j - 1] + triangle[i - 1][j]
+        triangle.append(row)
+    return triangle
+
+
+def print_triangle(triangle):
+    """Print the triangle centered, without brackets, commas or padding."""
+    rows = [" ".join(str(value) for value in row) for row in triangle]
+    width = len(rows[-1]) if rows else 0
+    for row in rows:
+        print(row.center(width))
+
+
+if __name__ == "__main__":
+    n = 5
+    print_triangle(pascals_triangle(n))