28 Mar
2017
28 Mar
'17
10:30 a.m.
If f(2*x)=2*f(x)+b*f(x)^3, then we can substitute x=2^(y-1): f(2*2^(y-1))=2*f(2^(y-1))+b*f(2^(y-1))^3, so f(2^y) = 2*f(2^(y-1)) + b*f(2^(y-1))^3, so if g(y)=f(2^y) then g(y) = 2*g(y-1) + b*g(y-1)^3 So how do we solve this non-linear recurrence relation for g(y)?