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Bob Bridges[_2_] Bob Bridges[_2_] is offline
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Default 如何*總算出sigma(1到n)

I'm not sure what you mean by "*總", jefferson. In general the formula for 總和
i (m 到 n) ought to be

n(n+1)/2 - (m-1)m/2

....which comes out to

(n**2 - m**2 + m + n)/2

I'm not aware of any Excel function that does that calculation for you.

--- "jefferson" wrote:
在Excel如何*總算出 sigma (1 到 n),
不使用儲**,要能直接在儲**內輸 公式而得到*總值的.
例如:
sigma(1,3)=6 *為 1+2+3 = 6

sigma(2,5)=14 *為 2+3+4+5 = 14