a(-1)=0. a(n)=a(n-1)^2+2^n.A168320a(-1)=0. a(n)=a(n-1)^2+2^n.Terms a(0) =1a(1) =3a(2) =13a(3) =177a(4) =31345a(5) =982509057External referencesoeis: A168320