Number of samples in a discrete signals after sampling a continuous periodic signal should be integer?
There is nothing unordinary about it. Signals can have a period that is not an integer multiple of samples, and that is normal. For example, if you record a 440 Hz sine wave with a sampling rate of 48 kHz, it is not an integer multiple. It takes 11 full sine wave periods to hit an integer amount of 1200 samples.