ekke, thank u. one more doubt, http://www.nabble.com/file/p14592492/febb.jpeg In the above fibonacci example(Adiut view for n=4), 1 . After object updated : fibonacci(1,1) why activation created and cancelled for fibonacci(3,2,1,4) ? 2 . After object updated : fibonacci(2,1) why activation not created and cancelled? 3 . In calculate rule , How it applies fibonacci object ie fibonacci(1,1)-->fibonacci(2,1)-->fibonacci(3,-1) in order after that fibonacci(2,1)-->fibonacci(3,2)-->fibonacci(4,-1) in order. -- View this message in context: http://www.nabble.com/Flow-of-rules---tp14573971p14592492.html Sent from the drools - user mailing list archive at Nabble.com.