12^13(3^10*4^11)
=12^13(3^10*4^10*4)
=12^13(12^10*4)
=12^23*4
(5^4*3^3-5^3*3^2+5^2*3)/15
=5^2*3(5^2*3^2-5*3+1)/15
=5*(225-15+1)
=5*211
=1055