00:01
In this problem, we need to determine how many sequences of seven turnary digits are possible, containing a single zero and a single chip.
00:08
So we need a sequence of seven digits, so one, two, three, four, five, six, seven.
00:15
And the sequence needs to have exactly one zero and exactly one two.
00:19
So we just need to choose any two positions and put a zero and two.
00:23
Now, since there is only one other turnary digit, that is one.
00:28
That means when we choose the positions for the zero and two, automatically, the rest of them are going to become one, and we will get a sequence.
00:36
So in order to determine the different sequences, all we need to do is choose any two positions and places zero and two in those two positions.
00:44
Now, the order matters in this case, because if we have a sequence like this versus if we have a sequence like this, where the positions of two and zero are interchains, then we get different sequences.
00:54
So that means out of seven positions, we need to choose any two positions...
