QBasic -如何获取F的值

Question

我有以下公式：

F =  X / 1+4+9+16+....+n^2

如何用QBasic编写程序来查找F的结果

谢谢。

Answer 1

在this useful page中，前n个自然数的平方和为：

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所以你只需要计算一下：

F = X * 6 / (n * (n + 1) * (2 * n + 1))

Answer 2

CLS
INPUT "Input the value of n: ", n%
INPUT "The value of X: ", X
denominator% = 0
FOR i% = 1 TO n%
    denominator% = denominator% + i% ^ 2
NEXT i%
F = X / denominator%
PRINT "F = "; F

Answer 3

一个乘法器：

DEFDBL A-Z
INPUT "Input the value of n: ", n
INPUT "The value of X: ", X
INPUT "The power: ", p
denominator = 0
FOR i = 1 TO n
    denominator = denominator + i ^ p
NEXT
F = X / denominator
PRINT "F = "; F
END