10. If the sequence $\left\{a_{n}\right\}$ has the first 6 terms as $1,0,1,0,1,0$, then a recurrence relation satisfied by the sequence $a_{n}$ is $\qquad$.
10. $a_{n}+a_{n+1}=1(n \geqslant 1)$ or $a_{n+1}-a_{n}=(-1)^{n}$.