How to fill in after 65 37 17 () is a question of testing IQ I can't find the rules. I hope GG mm can help me find them,

How to fill in after 65 37 17 () is a question of testing IQ I can't find the rules. I hope GG mm can help me find them,

an=(10-2n)^2+1
65、 37、 17、 ( 5)、 1、 5 ...