The sequence is given by the recurrent formula a1 = 0 a2 = 1 …, an + 2 = an + 1-an

The sequence is given by the recurrent formula a1 = 0 a2 = 1 …, an + 2 = an + 1-an find the 885th term of this sequence.

According to the condition of the problem, this sequence is given by the recursive formula an + 2 = an + 1 – an.

Therefore, for the n + 1th term, the following relation holds:

an + 1 = an – an-1.

Substituting the found value for the n + 1-th term in the formula for the n + 2-th term, we get:

an + 2 = an + 1 – an = an – an-1 – an = -an-1.

Reasoning in the same way, we get:

an-1 = -аn-4,

whence it follows that

an + 2 = -an = – (- an-4) = an-4.

Then for n = 883 we get:

a885 = a879,

and applying the formula an + 2 = an-2 for n = 877, 871, 885, …, 9, 3, we get:

a885 = a879 = a873 = a867 = … = a11 = a5.

We find a5:

a5 = a4 – a3 = a3 – a2 – a3 = -a2 = -1.

Therefore, a885 = -1.

Answer: a885 = 1.