Someone suggests a new way to create infinite numbers each greater than any positive constants from those Un--->0 items in Harmonic Series and turn the Un--->0 infinite Harmonic Series into a “Vn ---> any positive constants” infinite series (with infinite items each bigger than any positive constants, such as 100000000000000000000000000000)”:

Let x:=1000000000000000 - 1. That is 10^15 - 1, which is larger than 2^49 (calculator: 2-log(10^15) is 49.82892142). The sum of x terms following 1 is

1/2+1/3+...+1/(x+1) ≧ 1/2+1/3+...+1/2^49 (which has fewer terms to add).

Now I subdivide the sequence into 49 sub-sequences T_0, T_1, T_2, .. ,T_48, where T_i runs from 1/(2^i+1) to 2/2^(i+1), thus:

T_0:= (1/2),

T_1:=(1/3,1/4),

T_2:=(1/5,1/6.1/7,1/8) etc.

It is up to you to write the intermediate 45 sequences up to T_48:=(1/(2^48+1),...1/2^49).

A generic sequence T_i has 2^i terms and sums as 1/(2^i+1) + ... + 1/(2^(i+1). Replace each term by the last one, which is the smallest:

sum(T_i) ≧ sum of (2^i times 1/2^(i+1) ) = 1/2.

The sum of all terms from 1/2 to 1/x is larger than T_0+T_1+T_2+...+T_48, which is larger that 49 times 1/2. Therefore, the desired sum is at least 24.5 (25.5, if you insist on adding the first term, 1.)

If you consider x:=1000000000000000000000000000000 =10^30 with 2-log 99.65784285, you may copy the above argument with 99 sub-sequences, summing up to at least 99/2=49.5 (50.5, if you include the first term 1).

You can already see a proof that for each positive integer x:

1+1/2+ ... + 1/(x+1) ≧ 1 + 1/2 times ( integer part of the 2-log of (x+1) ).

This matches well with a known result in calculus approximating this sum with ln(1+x).

Do you agree with it and why?

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