Declension table of ?nāśyatva

Neuter	Singular	Dual	Plural
Nominative	nāśyatvam	nāśyatve	nāśyatvāni
Vocative	nāśyatva	nāśyatve	nāśyatvāni
Accusative	nāśyatvam	nāśyatve	nāśyatvāni
Instrumental	nāśyatvena	nāśyatvābhyām	nāśyatvaiḥ
Dative	nāśyatvāya	nāśyatvābhyām	nāśyatvebhyaḥ
Ablative	nāśyatvāt	nāśyatvābhyām	nāśyatvebhyaḥ
Genitive	nāśyatvasya	nāśyatvayoḥ	nāśyatvānām
Locative	nāśyatve	nāśyatvayoḥ	nāśyatveṣu

Compound nāśyatva -

Adverb -nāśyatvam -nāśyatvāt