2005^2+2006^2*2005^2+2006^2
=2005^2+(2005+1)^2*2005^2+2006^2
=2005^2+2005^4+2*2005^3+2005^2+2006^2
=2005^4+(2*2005+2)*2005^2+2006^2
=2005^4+2*2006*2005^2+2006^2
=(2005^2+2006)^2
2005^2+2006^2*2005^2+2006^2
=2005^2+(2005+1)^2*2005^2+2006^2
=2005^2+2005^4+2*2005^3+2005^2+2006^2
=2005^4+(2*2005+2)*2005^2+2006^2
=2005^4+2*2006*2005^2+2006^2
=(2005^2+2006)^2