Declension table of ?yatprathama

Neuter	Singular	Dual	Plural
Nominative	yatprathamam	yatprathame	yatprathamāni
Vocative	yatprathama	yatprathame	yatprathamāni
Accusative	yatprathamam	yatprathame	yatprathamāni
Instrumental	yatprathamena	yatprathamābhyām	yatprathamaiḥ
Dative	yatprathamāya	yatprathamābhyām	yatprathamebhyaḥ
Ablative	yatprathamāt	yatprathamābhyām	yatprathamebhyaḥ
Genitive	yatprathamasya	yatprathamayoḥ	yatprathamānām
Locative	yatprathame	yatprathamayoḥ	yatprathameṣu

Compound yatprathama -

Adverb -yatprathamam -yatprathamāt