every Nth column cell entry should be red , every Nth+1 column cell should be blue

[Pankaj16]

Dear All I need a code or short cut to asign a red color for all the cell coming in column (1st,4th,7th, (n+3)...............) and blue color for the cell for column ( 2nd,5th,8th,(n+1)........)

kindly help me

 

[Hui]

Have a read of:
http://chandoo.org/wp/2011/12/08/formula-forensics-no-005/

 

[Hui]

I'd use a Conditional Formatting using a Formula of:
=MOD(COLUMN(),3)=1 Blue
=MOD(COLUMN(),3)=2 Red

 

[Pankaj16]

Thanks alot.......... I really appreciate to your work.