Declension table of ?pañcasasya

Neuter	Singular	Dual	Plural
Nominative	pañcasasyam	pañcasasye	pañcasasyāni
Vocative	pañcasasya	pañcasasye	pañcasasyāni
Accusative	pañcasasyam	pañcasasye	pañcasasyāni
Instrumental	pañcasasyena	pañcasasyābhyām	pañcasasyaiḥ
Dative	pañcasasyāya	pañcasasyābhyām	pañcasasyebhyaḥ
Ablative	pañcasasyāt	pañcasasyābhyām	pañcasasyebhyaḥ
Genitive	pañcasasyasya	pañcasasyayoḥ	pañcasasyānām
Locative	pañcasasye	pañcasasyayoḥ	pañcasasyeṣu

Compound pañcasasya -

Adverb -pañcasasyam -pañcasasyāt