5.1. Convergence Regularity of Complement Weight Function
To avoid proving weight function W[a] converging to 0(it is not easily to prove strictly the numerator part must be equal to 0 finally), build its complement weight function. Build:
, the highest bit of a is 2m.
Through the proof and introduction above, we know Wc[a] monotonically increases except when corresponding odd bi in sequence of ai is 1 or 3, and these exception cases are not worth worrying about. And we also know the convergence state of Wc[a] is .
Suppose odd a0, a1, a2 are three elements in order in sequence, a0 is equal to a, then
, , , where 2p is 2k in first step operation.
, ,
Observe this formula, when 2p is equal to 2 or 4, is , suppose this ratio is , then
,
When n->∞, , this is a convergence state, in actual case, it needs a limit number n steps to reach to(or bigger than) , because the ratio is .
when 2p is bigger than 4, is , but still , Wc[a] also increases, Wc[a] can converge in (k is any positive integer), not only . This increases the convergence chance of Wc[a].
Observe the varying of fraction in lowest terms of Wc[a], the denominator part is equal, smaller, or 2 times of previous(because the numerator part at least can be divided by 2 in each step) in each step, when is equal, the numerator part should increase, it is possible to converge, when is 2 times of previous, the total value also increase, when is smaller, the total value should not only be bigger than the value of front Wc[a] with same denominator part(if exists), but also be bigger than all Wc[a] follow it. And in long sequence, usually appear smaller case, it has many chances to appear , especially when the front element is already close to its convergence state. For example, suppose 177/256 is in sequence, if some following element with same denominator part 256 appear after many steps, its value should be bigger than all the elements between 177/256 and itself, it is much possible to be equal to 255/256.
Continuously observe Wc[a], even in the 2 times case, elements are closer to convergence state by themselves. Suppose the denominator part of fraction in lowest terms of is 2m+2,
2m<a<2m+1-1, if a is not equal to 11…101, which is very close to its convergence state 11…1, the above formula is <0. Thus prove the above conclusion.
Below give an example of start number 27 in odd sequence to verify, some decimals are written in the form which is easily to be judged equal to, bigger or smaller than 0.75.
Odds in sequence are:
37,87,97,209,441,917,1887,1927,1957,3959,3993,8037,16151,16209,32505,65141,130479,130627,65369,130821,261767,261861,523863,523969,1048097,2096433,4193225,8386989,16774787,8387697,16775849,33552381,67105787,16776639,16776783,16776891,4194243,2097129,4194269,8388555,1048571,262143
Wc[a] sequence:
37/64,87/128,97/128,209/256,441/512,917/1024,1887/2048,1927/2048,1957/2048,3959/4096,3993/4096,8037/8192,16151/16384,16209/16384,32505/32768,65141/65536,130479/(65536*2),130627/(65536*2),65369/65536,130821/(65536*2),261767/(65536*4),261861/(65536*4),523863/(65536*8),523969/(65536*8),1048097/(65536*16),2096433/(65536*32),4193225/(65536*64),8386989/(65536*128),16774787/(65536*256),8387697/(65536*128),16775849/(65536*256),33552381/(65536*512),67105787/(65536*1024),16776639/(65536*256),16776783/(65536*256),16776891/(65536*256),4194243/(65536*64),2097129/(65536*32),4194269/(65536*64),8388555/(65536*128),1048571/(65536*16),262143/262144
sequence:
13/128,10/128,15/256,23/512,35/1024,53/2048,40/2048,30/2048,45/4096,34/4096,51/8192,77/16384,58/16384,87/32768,131/65536,197/(65536*2),148/(65536*2),111/(65536*2),83/(65536*2),125/(65536*4),94/(65536*4),141/(65536*8),106/(65536*8),159/(65536*16),239/(65536*32),359/(65536*64),539/(65536*128),809/(65536*256),607/(65536*256),455/(65536*256),683/(65536*512),1025/(65536*1024),769/(65536*1024),144/(65536*256),108/(65536*256),81/(65536*256),15/(65536*64),11/(65536*64),17/(65536*128),13/(65536*128),1/(65536*16)
sequence:
10/13≈0.77,0.75,0.77,0.76,0.76,0.755,0.75,0.75,0.76,0.75,0.755,0.753,0.75,0.753,0.752,0.751,0.75,0.748,0.753,0.752,0.75,0.752,0.75,0.752,0.751,0.751,0.750,0.750,0.749,0.751,0.750,0.750,0.749,0.75,0.75,0.741,0.73,0.77,0.76,0.62