crazy eights vs seven

crazy eights

noun
  • A card game in which players try to rid themselves of their cards by playing a matching rank or suit on the previous card played, having to draw an additional card if unable to do this; a player who plays an eight can dictate the suit to be played next. 

seven

noun
  • A card bearing seven pips. 

  • The digit/figure 7 or an occurrence thereof. 

num
  • A numerical value equal to 7; the number following six and preceding eight. This many dots: (•••••••). Describing a group or set with seven elements. 

How often have the words crazy eights and seven occurred in a corpus of books? (source: Google Ngram Viewer )