Declension table of ?ṛkva

Masculine	Singular	Dual	Plural
Nominative	ṛkvaḥ	ṛkvau	ṛkvāḥ
Vocative	ṛkva	ṛkvau	ṛkvāḥ
Accusative	ṛkvam	ṛkvau	ṛkvān
Instrumental	ṛkveṇa	ṛkvābhyām	ṛkvaiḥ ṛkvebhiḥ
Dative	ṛkvāya	ṛkvābhyām	ṛkvebhyaḥ
Ablative	ṛkvāt	ṛkvābhyām	ṛkvebhyaḥ
Genitive	ṛkvasya	ṛkvayoḥ	ṛkvāṇām
Locative	ṛkve	ṛkvayoḥ	ṛkveṣu

Compound ṛkva -

Adverb -ṛkvam -ṛkvāt