−𝐹 生成负斐波那契数Generate NegaFibonacci Numbers
生成负下标斐波那契数：F_{-n}=(-1)^{n+1} F_n。可设个数与起始负下标，本地处理。Generate negative-index Fibonacci numbers: F_{-n}=(-1)^{n+1} F_n. Set count and start index. Processed locally.
使用说明与常见问题How-to & FAQ
「生成负斐波那契数」是什么？What is the Generate NegaFibonacci Numbers tool?
生成负下标斐波那契数：F_{-n}=(-1)^{n+1} F_n。可设个数与起始负下标，本地处理。Generate negative-index Fibonacci numbers: F_{-n}=(-1)^{n+1} F_n. Set count and start index. Processed locally.
如何使用「生成负斐波那契数」？How do I use the Generate NegaFibonacci Numbers tool?
在「生成负斐波那契数」中，按需设置「项数」、「起点下标（负）」，结果会实时显示在下方，点击「复制结果」即可复制。In the Generate NegaFibonacci Numbers: Adjust "Terms", "Start index (negative)"; the result appears below instantly — click "Copy result" to copy it.
负下标的斐波那契数正负号怎么定？How is the sign of negative-index Fibonacci numbers decided?
F_{-n}=(-1)^{n+1} F_n，例如 F_{-1}=1，F_{-2}=-1。F_{-n}=(-1)^{n+1} F_n, e.g. F_{-1}=1, F_{-2}=-1.
输入和输出是什么样的？What does the input and output look like?
例如在「生成负斐波那契数」中把「项数」设为 4，「起点下标（负）」设为 -1，输出为：1 ⏎ -1 ⏎ 2 ⏎ -3（⏎ 表示换行）。For example, in the Generate NegaFibonacci Numbers with "Terms" set to 4, "Start index (negative)" set to -1, the output is: 1 ⏎ -1 ⏎ 2 ⏎ -3 (⏎ marks a line break).
有哪些选项可以调整？What options can I adjust?
「生成负斐波那契数」的设置：「项数」默认 15；「起点下标（负）」默认 -1。每次生成结果都按当前设置处理。Settings in the Generate NegaFibonacci Numbers — "Terms" default 15; "Start index (negative)" default -1. The result always uses the current settings.
计算精度如何？How precise are the results?
「生成负斐波那契数」中的整数都用大整数（BigInt）精确计算，不经过浮点，所以再长的项也不会丢失位数；输入超出页面说明的范围时会给出提示，而不是悄悄截断。Integers in the Generate NegaFibonacci Numbers are computed exactly with big integers (BigInt), with no floating-point step, so even very long terms keep every digit; values outside the stated ranges give a message instead of being silently cut off.
「生成负斐波那契数」免费吗？需要注册吗？Is the Generate NegaFibonacci Numbers free? Do I need an account?
「生成负斐波那契数」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Generate NegaFibonacci Numbers is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.