00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000600000000000000000060000000000000000000000000000000000000000000000000000000000000000000000000000000000
Có bao nhiêu chữ số 6 và các chữ số 6 đó nằm ở chỗ nào ?