#恒等式

拉马努金恒等式

证明就是反复利用平方差公式:n=1+(n−1)⋅(n+1)−−−−−−−−−−−−−−−−−√f(x)=1+x1+(x+1)1+(x+2)1+...−−−−−√−−−−−−−−−−−−−−−−√−−−−−−−−−−−−−−−−−−−−−−−−−−−√−−−−−−−−−−−−−−−−−−−−−−−−−−−−−√−−−−−...
代码星球 ·2020-04-15