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主要内容

第n个词测试

问题

sum, start subscript, n, equals, 1, end subscript, start superscript, infinity, end superscript, start fraction, left parenthesis, 2, n, minus, 3, right parenthesis, left parenthesis, n, start superscript, 8, end superscript, plus, 1, right parenthesis, squared, divided by, left parenthesis, 6, minus, 5, n, right parenthesis, squared, left parenthesis, 4, minus, 3, n, squared, right parenthesis, squared, end fraction
可以通过第n项测试得出什么结论?
选出正确答案:
不会做了?
不会做了?