在vf中,用FOR循环语句编程求2!＋4!＋…＋（2n）!,其中i!

public t
input "n=" to n
sum=0
for i=1 to n
do p with i
sum=sum+t
emdfor
sum
return
procedure p
para i
t=1
for j=1 to 2*i
t=t*j
endfor
endproc