Dear Sir, I think in Tamilnadu, Tanjore District, Thiruvayyaaru where (Thyagaraja Aaradhanai Utchavam) is celebrated every year in Pushya masam; The main Deity in Thiruvayyarru is Lord Panchapakesan ( in Tamil Iyyaarappan) Here the river Cauvery is split into five branches before joining in sea So it is called Thiruvayyaaru ( in Sanskrit Punjab ( of Southern part) So, generally Brahmins from this Tanjore, Thiruvayyaru male children are named Panchapakesan or Chettiars Panchanatham chettiars