a(0)=1, a(n+1)=1+(2^(2^n)+1)*a(n).A048164a(0)=1, a(n+1)=1+(2^(2^n)+1)*a(n).Terms a(0) =1a(1) =4a(2) =21a(3) =358a(4) =92007a(5) =6029862760External referencesoeis: A048164