1234 + 1243 + 1342 + 1324 + 1423 + 1432 + 2134 + 2143 + 2341 + 2314 + 2413 + 2431 + 3214 + 3241 + 3124 + 3142 + 3412 + 3421 + 4321 + 4312 + 4213 + 4231 + 4123 + 4132 = 66660
tong cua tat ca cac so tu nhien co 4 chu so khac nhau duoc viet boi cac chu so 1,2,3,4
tong cua tat ca cac so tu nhien co 4 chu so khac nhau duoc viet boi so 1,2,3,4
tong cua tat ca cac so tu nhien co 4 chu so khac nhau duoc viet boi ca cac chu so 1, 2, 3, 4,
tong cua so tu nhien co 4 chu so khac nhau duoc viet boi cac chu so 1,2,3,4 la
tong cua tat ca cac so co 4 chu so khac nhau doc viet tu 1;2;3;4
tim so tu nhien lon nhat co chu so khac nhau biet so do bang tong tat ca cac so co hai chu so khac nhau duoc lap tu chu so cua so do
tim so tu nhien lon nhat co chu so khac nhau biet so do bang tong tat ca cac so co hai chu so khac nhau duoc lap tu chu so cua so do
tim so tu nhien lon nhat co chu so khac nhau biet so do bang tong tat ca cac so co hai chu so khac nhau duoc lap tu chu so cua so do
tim so tu nhien lon nhat co3 chu so khac nhau biet rang so do bang tong tat ca cac so co hai chu so khac nhau duoc lap tu ba chu so cua so do
