Maxima hangs while implementing commands



Hi guys, I think I found a bug in maxima:
While randomly trying some commands, I've entered 2 commands that made
maxima hanging up:

1) grind(trigsimp(trigexpand(a*k*a*i*cot(1401*(%e)))));
2) grind(trigrat(a*k*a*i*cot(%e)^1401));

Could you please tell me if that's really a bug or it's just a long
calculation process. I've waited for a minute, but nothing happened
and my CPU load was 100%

My Maxima version is 5.17.1

Regards,
Nguyen Duc Ngoc