kpoints for Dos calculation

[wot19920302]

Dear Quantumstaffs:
           I want to calculate  DOS of nanotube unitcell. Because of 1D system, the K-pionts for electronic structures calculation  is 1*1*21 ,if I want to cauculate DOS(It seems that kpoints used for DOS should be larger than  electronic structures calculation ),  what kpionts should be?
           Best

[Anders Blom]

1x1x23
No, you simply need to increase it until you don't see any change, same as how you found out 21 was sufficient for the electron density to converge.