n=ab0+1ab+2x6ab
n=100xa+10xb+0+100+10xa+b+2x(600+10xa+b)
n=110xa+11xb+100+1200+20xa+2xb
n=130xa+13xb+1300
n=13x(10xa+b+100)
daca n=cu un cub perfect,inseamna:
n=13x13x13
=>10xa+b+100=13x13
10xa+b+100=169
10xa+b=169-100
10xa+b=69
10xa+b=10x6+9
=>a=6 si b=9
