CH3 - CH(CH3) - CH(CH3) - CH2 - CH(CH3) - CH2 - CH2 - CH2 - CH2 - CH3
CH3 - CH(CH3) - CH2 - CH(CH3) - CH(CH2-CH3) - CH2 - CH2 - CH3
CH3 - CH(CH3) - CH(CH3) - CH2 - CH(CH3) - CH2 - CH2 - CH2 - CH2 - CH3
CH3 - CH(CH3) - CH2 - CH(CH3) - CH(CH2-CH3) - CH2 - CH2 - CH3