In the chandas (Vedas) we have the following irregular participles - 1. nasatta 2. niṣatta 3. anutta 4. pratūrta 5. sūrtta and 6. gūrtta,
The words नसत्त and निषत्त are derived from the root सद् preceded by न and नि, and there is not the न change of 8.2.42. Thus नसत्तमञ्जसा ॥ In secular literature we have नसन्नम् ॥ So also निषत्तः in the Vedas, but निषण्णः in secular literature. The word अनुत्तः is from उन्द with the negative अन् ॥ The option of 8.2.56 does not apply here. As अनुत्तमा ते मघवन् (= अनुन्नम्) ॥ प्रतूर्त्तम् is from त्वर् or तूर्व, as प्रतूर्त्तं वाजिनम् (= प्रतूर्णम्) ॥ When it is derived from त्वर् then ऊठ् is added by 6.4.20; and when from तूर्व then 6.4.21 is applied. सूर्त्ते is from सृ, the ऋ is changed to उ irregularly, as सूर्त्तागावः = सृतागावः ॥ गूर्त्तं is from गूर्, as गूर्त्ता अमृतस्य (= गूर्णे) ॥,