Prime Signature

Author

Eric W. Weisstein
May 5, 2006

This notebook downloaded from http://mathworld.wolfram.com/notebooks/PrimeNumbers/PrimeSignature.nb.

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

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

Initialization

PrimeSignature[1]:={1}

PrimeSignature[n_Integer?Positive]:=Sort[Transpose[FactorInteger[n]][[2]]]

Examples

{#,PrimeSignature[#]}&/@Range[20]//ColumnForm

sig=PrimeSignature/@Range[1000];

{#,Position[sig,#]//Flatten}&/@Union[sig]//ColumnForm

Sequences

PrimeSignature/@Range[10]

Flatten[PrimeSignature/@Range[20]]