"The number is ZERO..........."The number is ZERO...........
Explanation:
Co^(3+)Co3+ has a d^6d6 electronic configuration.......and these are classically LOW SPIN, especially with strong field ligands such as cyanide.........
[Co(C-=N)_6]^(3-)[Co(C≡N)6]3− is thus diamagnetic with no unpaired electrons.