وَمَا خَلَقْتُ الْجِنَّ وَالْإِنْسَ إِلَّا لِيَعْبُدُونِ
“I created jinn and humans only so that they may worship Me.” (Adh-Dhariyat 51:56)
The ordinary second-group form is يَعْبُدُونَ, whose inflectional nūn is removed after the purpose lām. The visible nūn in لِيَعْبُدُونِ is a different protective nūn connected with the omitted first-person object yā. Therefore it does not contradict the nūn-deletion rule.