%D A036434 %D A036438 Colton, "Refactorable Numbers - A machine invention", to be submitted to the online journal of integer sequences Simon Colton: Refactorable Numbers - A Machine Invention Journal of Integer Sequences, Vol.2 (1999), Article 99.1.2 http://www.research.att.com/~njas/sequences/JIS/colton/joisol.html APH