1)当q=1时,a(n+1) -an =pn+man- a(n-1) =p(n-1) +m..a2-a1= p+man -a1 =pn(n-1)/2 +m(n-1)an =1+pn(n-1)/2 +m(n-1)2) 当q≠1时 设 a(n+1)+x(n+1）+y=q[an +xn +y] 等比数列 展开,比较系数,得x=p/(q-1),y=(p+mq-m)/(q...