→ yclinpa : 直接用 Bolzano-Weirstrass 定理就可以了 10/08 06:14
Let r1,r2,......be real numbers. For any indices i and j with 1 <= i < j
def
,let r(i,j) = ri + ri+1 + ... +rj-1.
if there is a positive integer m with r(1,j) <= m
for any interger j >= 2 , then there is a positive integer k with
r(k,j) < 1/2
for any integer j > k
How to prove it ?
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