Question

Consider this sequence

Answer 1

Hello,

$u_{1} =1*(8-7)=1*(2*4-(6+1))\\ u_{2} =2*(10-7)=2*(2*5-(6+2))=2*(2*(4+1)-(6+2))\\ u_{3} =3*(12-9)=3*(2*6-(6+3))=3*(2*(4+2)-(6+3))\\ u_{4} =4*(14-10)=4*(2*7-(6+4))=4*(2*(4+3)-(6+4))$


$u_{10}=10*(2*(4+10)-(6+10))\\ =10*(28-16)$

$...\\\\ u_{n} =n*(2*(n+n-1)-(6+n))\\ =n*(4n-2-6-n)=n(3n-8)$