Untouchable Number

Author

Eric W. Weisstein
August 3, 2006

This notebook downloaded from http://mathworld.wolfram.com/notebooks/IntegerSequences/UntouchableNumber.nb.

For more information, see Eric's MathWorld entry http://mathworld.wolfram.com/UntouchableNumber.html.

©2006 Wolfram Research, Inc. except for portions noted otherwise

Enumeration

Complement[Range[200],Union[Total[Most[Divisors[#]]]&/@Range[10^5]]
]