3.4.65

शकधृषज्ञाग्लाघटरभलभक्रमसहार्हास्त्यर्थेषु तुमुन्

Laghu-siddhāntakaumudī does not carry this rule. It stands in the Aṣṭādhyāyī at 3.4.65, and the abridgement is 1,269 of Pāṇini's 3,983 rules — so this is a place where the poem runs past the textbook.

तुमुन् (the infinitive) after a root governed by शक् "be able", अर्ह "deserve" and the like

When a root is governed by a word meaning "be able" (शक्), "dare" (धृष्), "know how" (ज्ञा), "be weary" (glai), "endeavour" (ghaṭ, rabh, labh, kram), "bear" (sah), "deserve" (arh), or "there is / ought", it takes the affix तुमुन्, giving the infinitive in -तुम्: गन्तुं शक्नोति "is able to go", द्रष्टुम् इच्छति "wishes to see". The infinitive is indeclinable. This rule stands outside the Laghu-siddhāntakaumudī abridgement's 1,269 sūtras.

• Aṣṭādhyāyī — 3.4.65 शकधृषज्ञाग्लाघटरभलभक्रमसहार्हास्त्यर्थेषु तुमुन्
• Siddhāntakaumudī — तुमुन् prakaraṇa; the infinitive stands outside Laghu-siddhāntakaumudī’s 1,269 sūtras

uncheckeddrafted from the rule text