FactorInteger[1] == {}
Cell[BoxData[RowBox[List[RowBox[List["FactorInteger", "[", "1", "]"]], "\[Equal]", RowBox[List["{", "}"]]]]]]
<math xmlns='http://www.w3.org/1998/Math/MathML' mathematica:form='TraditionalForm' xmlns:mathematica='http://www.wolfram.com/XML/'> <semantics> <mrow> <mrow> <mi> factors </mi> <mo> ⁡ </mo> <mo> ( </mo> <mn> 1 </mn> <mo> ) </mo> </mrow> <mo> ⩵ </mo> <mrow> <mo> { </mo> <mo> } </mo> </mrow> </mrow> <annotation-xml encoding='MathML-Content'> <apply> <eq /> <apply> <ci> factors </ci> <cn type='integer'> 1 </cn> </apply> <list /> </apply> </annotation-xml> </semantics> </math>
Cell[BoxData[RowBox[List[RowBox[List["HoldPattern", "[", RowBox[List["FactorInteger", "[", "1", "]"]], "]"]], "\[RuleDelayed]", RowBox[List["{", "}"]]]]]]
2001-10-29