The isoelectronic species have a similar bond order.

Both CN^- and NO⁺ have 14 electrons.

Both CN^- and NO⁺ have identical bond order i.e. 3.

(MOT diagram of CN^-)

So, from the above diagram in CN^-,

Electrons in bonding molecular orbitals = 8

Electrons in Anti Bonding Molecular orbitals = 2

Bond Order = .

= (8-2)

= 3

So, from the above MOT diagram of NO⁺,

Electrons in bonding molecular orbitals = 10(2e^- in 1s)

Electrons in Anti Bonding Molecular orbitals = 4(2e^- in 1*s)

Bond Order = .

= (10-4)

= 3.