05AB1E, 17 bytes

FLN+I·¸«ˆ}·¸I>.׈

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05AB1E, 17 bytes

FLN+I·¸«ˆ}·¸I>.׈

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Explanation

F                   # for N in [0 ... input-1]
 L                  # push range [1 ... input]
  N+                # add N to each
    I·¸«            # append input*2
        ˆ           # add to global list
         }          # end loop
          ·¸        # push [input*2]
            I>.×    # repeat it input+1 times
                ˆ   # add to global list
                    # implicitly output global list