User Portlet User Portlet

Discussions
Thank you for your help! I tried that Nestlist-function but I am not sure that this gives me what I want... or mayby I dont know how to use it. But let say that I want to iterate x^2+b of 2 times NestList[x, x^2 + a, 2] {a + x^2, x[a + x^2], x[x[a...