Hamsanadam
A Prati Madhyama raga often heard today in a five-note form without Ga or Dha.
Hamsanadam’s commonly heard five-note outline combines Ri, the higher Ma, Pa and the higher Ni. Ga and Dha are absent from this five-note outline.
Scale
Arohana: S R2 M2 P N3 Ṡ
Avarohana: Ṡ N3 P M2 R2 S
It is conventionally classified under Neetimati, Melakarta 60. R2 is Chatusruti Rishabha, M2 Prati Madhyama and N3 Kakali Nishada.
Recognising the movement
The move from Ri to Ma leaves out Ga; the move from Pa to Ni leaves out Dha. Compare Hamsadhwani, which has Ga instead of Ma. Similar names do not mean the same notes or melodic identity.
Older forms of Hamsanadam also use D3, Shatsruti Dhaivata; the five-note form omits it.
Compositions
Bantureeti Koluvu by Tyagaraja is a useful place to begin. Follow its recurring appeal for service to Rama while listening for the Ri–Ma and Pa–Ni relationships.