[1!+2!+3!+ +n!]/n! ＝1+1/n+1/[n(n-1)]+1/[n(n-1)(n-2)]+...+1/n!<=1+1/n+1/[n(n-1)]*(n-2)
<=1+1/n+1/n;
[1!+2!+3!+ +n!]/n!>1
由迫敛性可知结果为1.