有求任意随机数的公式吗？

都说是任意随机啦，怎么可能会有。

(Math.random())

=CONCATENATE(RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9),RANDBETWEEN(0,9)) 这是20位的随机数.

EXCEl中，RAND()是取0~1之间的随机数的函数；RANDBETWEEN(N,M)是取指定的[n,m]区间的随机数的函数。如：
=RAND()*20 则取小于20的随机数
=INT(RAND()*20) 则取小于20的随机整数
=RANDBETWEEN(100,1000) 则取100~1000之间的随机数
RAND()和RANDBETWEEN()函数的转换（因为有些版本没有randbetwwen()函数）
RANDBETWEEN(100,1000)=INT(RAND()*(1000-100))+100
即：randbetween(n,m)=rand()*(m-n)+n (如果要整数，加INT()函数即可）