notionnoughtnowhere densenowhere dense setnozzlenozzle tipnp chartnthnth coordinatenth derivativenth factornth iteratenth order differential equationnth partial productnth partial sumnth powernth rootnth root functionnth root of unitynth termnth variationnuclearnuclear classnuclear fissionnuclear operatornuclear reactionnuclear spacenuisance parameternullnull circlenull classnull elementnull eventnull functionnull graphnull groupnull hypothesisnull matrixnull quantifiernull recurrentnull sequencenull setnull setsnull spacenull stringnull treenull vectornullary operationnullitynullity of a linear mapping