Like all the other Avatars of Vishnu, the Narasimha Avatar is widely worshiped by Hindus; especially those from the Vaishnava Sampradaya.
There are some most powerful Narasimha Mantras in the Puranas; especially the Agni Purana, however care should be taken for the purpose one wishes to chant them. Those wishing to chant these mantras for Tamas Guni and selfish wants and desire, stay away as they may rebound back upon them.
The mantra given in this post is a mantra for those wishing to meditate on Narasimha. This mantra like most meditation mantras in a long-term one and only those wishing to meditate selflessly and purely without any ulterior motive need chant this mantra,
नृं नृं नृं नृसिंहाय नमः ||
Nruam Nruam Nruam Nrusiṃhaya Namah ||
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