Declension table of ?saptatantra

Neuter	Singular	Dual	Plural
Nominative	saptatantram	saptatantre	saptatantrāṇi
Vocative	saptatantra	saptatantre	saptatantrāṇi
Accusative	saptatantram	saptatantre	saptatantrāṇi
Instrumental	saptatantreṇa	saptatantrābhyām	saptatantraiḥ
Dative	saptatantrāya	saptatantrābhyām	saptatantrebhyaḥ
Ablative	saptatantrāt	saptatantrābhyām	saptatantrebhyaḥ
Genitive	saptatantrasya	saptatantrayoḥ	saptatantrāṇām
Locative	saptatantre	saptatantrayoḥ	saptatantreṣu

Compound saptatantra -

Adverb -saptatantram -saptatantrāt