Wilson, Robert G. (n.d.). "A016105: Blum integers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 22 April 2024.
Sloane, Neil; Steinerberger, Stefan (31 March 2006). "A005100: Deficient numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 22 April 2024.
Beedassy, Lekraj (7 January 2005). "A100832: Amenable numbers". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 22 April 2024.