That `butlast` removes the last three elements, but here you were supposed to remove the first three elements. So I guess `cdddr` is what you need.<p>Also, the way the article uses `remove-if-not` is all wrong. The `:start` argument to `remove-if-not` doesn&#x27;t mean it starts taking elements after the third one, rather it means it starts filtering after it. So<p><pre><code>  (remove-if-not #&#x27;evenp &#x27;(1 2 3 4 5 6) :start 3)
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doesn&#x27;t produce (4 6) as the article assumes. It produces (1 2 3 4 6).<p>And the `:count` argument doesn&#x27;t mean it returns 5 elements, rather it means it removes 5 elements. So<p><pre><code>  (remove-if-not #&#x27;evenp &#x27;(1 2 3 4 5 6) :count 1)
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returns (2 3 4 5 6).