oneth vs primigenial

oneth

adj
  • 'first', or other ordinal derivatives of 'one', such as hundred-and-oneth or minus-oneth 

  • Used at the end of algebraic expressions indicating ordinal position that end in 1, such as (k+1)ᵗʰ 

noun
  • A fractional part of an integer ending in one 

  • An ordinal value that is represented by an expression ending in 1 such as the (n + 1)th. 

primigenial

adj
  • First of all; firstborn; primary; original. 

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