若数列{a n }(n∈N + )为等差数列,则数列 b n = a 1 + a 2 + a 3 +…+ a n n (
1个回答
从商类比开方,从和类比到积,可得如下结论:
n C 1 C 2 C 3 C n
故答案为:
n C 1 C 2 C 3 C n
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