Slide number removal - yihui/xaringan GitHub Wiki

Usually you do not want to have a slide number on your title slide. There is a specific class in remark.js responsible for the slide number. You can change the setting for .title-slide by setting .remark-slide-number as a subclass of .title-slide and turn the particular setting off:

.title-slide .remark-slide-number {
  display: none;
}