indecomposable vs undecomposable

indecomposable

adj

  • Not decomposable: unable to be decomposed. 

noun

  • A vector space that cannot be decomposed. 

undecomposable

adj

  • Unable to be decomposed 

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