Question 305867
{{{P(7,3)=7!/(7-3)!=7!/4!=7*6*5=210}}}
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{{{ a1=e/1=e}}}
{{{a2=e^2/2}}}
{{{a3=e^3/3}}}
{{{a4=e^4/4}}}
{{{a5=e^5/5}}}