> This shows how it could be done using odd integers only. For
> explanation of terms see
Collatz.co.uk :
>
> Reworking of
Collatz.co.uk using odd integers
Ok, looking better.
>
> Step up functions 3o << 16o + 1
> 3e+1 << 4e + 1
> 3o+2 << 2o + 1
As I said, one of the ways I'm trying to understand this
is by converting it to the equivalent in my Sequence Vector
- Hailstone Function system (and I don't believe I have
anything equivalent to your nchains). Such conversion was
impossible and made no sense when you allowed 3n+1 operations
on even numbers and placed false nodes on the graph.
One other minor point: in my system, there is no such thing
as a "step up" from 3o as a 0(mod 3) can only appear in a
Collatz sequence if it starts with one. I insist that my
threads be invertable, that if I allow 9 << 49 then 49 >> 9
should also be legal, which it isn't. My Sequence Vector
data structure permits strict step downs using standard
Collatz rules n/2 & 3n+1 or strict step ups using inverse
rules n*2 & (n-1)/3. There is no provision for mixing
standard and inverse rules in a sequence as is required
to step up from a 0(mod 3) number to a "cousin" branch
of a childless parent.
Without an appropriate data structure, the Hailstone Function
parameters can't be calculated for the closed form expression
that is equivalent to your formulae above and completely
dispenses with the constructions you have in your appendices.
Hence, the insistence on strict directional rules.
Nevertheless, I CAN manually determine the formula for a single
step up to get the parameters, for ALL mod3 congruence classes.
I get:
for n==0(mod 3)
g__h
i
j__k note: if n==0(mod3) then j==1(mod3)
l
n__m
m = 3n + 1
l = 6n + 2
k = 12n + 4
j = 4n + 1
i = 8n + 2
h = 16n + 4
g = (16n + 3)/3
Now, g must be an integer, so we can write the RHS as a problem
in linear congruence:
16n == -3 (mod 3)
which, when solved, will give me integer values of n that result
in integer values of g. A linear congruence (in the form
Xn==Z(mod Y)) is solvable IF AND ONLY IF the gcd(X,Y) divides Z,
which it does.
Solving, using Python/gmpy
>>> import gmpy
>>> print gmpy.divm(-3,16,3) # linear congruence solver
0
So the first solution n(0) is 0. And if a linear congruence has a
first solution, it has an infinite number of them. The ith solution
is n(i) = Y*i + n(0), so the solution set of n is
n(i) = [0, 3, 6, 9, 12, ...]
but we only need the odd values.
n(i) = [3, 9, 15, 21, 27, ...]
To get the values they step up to, plug n(i) into (16n+3)/3 to get
g(i).
g(i) = [17, 49, 81, 113, 145, ...]
For n==1(mod 3)
g__l
m
n
m = 2n
l = 4n
g = (4n - 1)/3
4n == 1(mod 3)
>>> print gmpy.divm(1,4,3)
1
n(i) = [1, 7, 13, 19, 25, ...] # odds only
g(i) = [1, 9, 17, 25, 33, ...]
For n==2(mod 3)
g__m
n
m = 2n
g = (2n - 1)/3
2n == 1(mod 3)
>>> print gmpy.divm(1,2,3)
2
n(i) = [5, 11, 17, 23, 29, ...] # odds only
g(i) = [3, 7, 11, 15, 19, ...]
Note that the solution sets of the linear congruences prove that
every odd integer is on the graph. It does NOT imply that the
graph is connected.
One last thing. I want to check my generation calculator.
I would think it would work with the 0(mod 3) numbers since
it depends only on the Hailstone Function parameters which
I did manually for the step up. But have to only ask for
even members of the kth generation to get odds.
So, the first 33rd generation 0(mod 3) number would step
up to another 0(mod 3) number, which would step up to
another 0(mod 3) number, ... repeated 33 times.
My Python Collatz function library reports that it's
>>> print cf.geni(33,2,xyz)
6841920697299105
And we can check that it really does indeed step up 33
times before hitting a number not 0(mod 3):
1 : 6841920697299105
steps up to 36490243718928561 0 (mod 3)
2 : 36490243718928561
steps up to 194614633167618993 0 (mod 3)
3 : 194614633167618993
steps up to 1037944710227301297 0 (mod 3)
4 : 1037944710227301297
steps up to 5535705121212273585 0 (mod 3)
5 : 5535705121212273585
steps up to 29523760646465459121 0 (mod 3)
6 : 29523760646465459121
steps up to 157460056781149115313 0 (mod 3)
7 : 157460056781149115313
steps up to 839786969499461948337 0 (mod 3)
8 : 839786969499461948337
steps up to 4478863837330463724465 0 (mod 3)
9 : 4478863837330463724465
steps up to 23887273799095806530481 0 (mod 3)
10 : 23887273799095806530481
steps up to 127398793595177634829233 0 (mod 3)
11 : 127398793595177634829233
steps up to 679460232507614052422577 0 (mod 3)
12 : 679460232507614052422577
steps up to 3623787906707274946253745 0 (mod 3)
13 : 3623787906707274946253745
steps up to 19326868835772133046686641 0 (mod 3)
14 : 19326868835772133046686641
steps up to 103076633790784709582328753 0 (mod 3)
15 : 103076633790784709582328753
steps up to 549742046884185117772420017 0 (mod 3)
16 : 549742046884185117772420017
steps up to 2931957583382320628119573425 0 (mod 3)
17 : 2931957583382320628119573425
steps up to 15637107111372376683304391601 0 (mod 3)
18 : 15637107111372376683304391601
steps up to 83397904593986008977623421873 0 (mod 3)
19 : 83397904593986008977623421873
steps up to 444788824501258714547324916657 0 (mod 3)
20 : 444788824501258714547324916657
steps up to 2372207064006713144252399555505 0 (mod 3)
21 : 2372207064006713144252399555505
steps up to 12651771008035803436012797629361 0 (mod 3)
22 : 12651771008035803436012797629361
steps up to 67476112042857618325401587356593 0 (mod 3)
23 : 67476112042857618325401587356593
steps up to 359872597561907297735475132568497 0 (mod 3)
24 : 359872597561907297735475132568497
steps up to 1919320520330172254589200707031985 0 (mod 3)
25 : 1919320520330172254589200707031985
steps up to 10236376108427585357809070437503921 0 (mod 3)
26 : 10236376108427585357809070437503921
steps up to 54594005911613788574981709000020913 0 (mod 3)
27 : 54594005911613788574981709000020913
steps up to 291168031528606872399902448000111537 0 (mod 3)
28 : 291168031528606872399902448000111537
steps up to 1552896168152569986132813056000594865 0 (mod 3)
29 : 1552896168152569986132813056000594865
steps up to 8282112896813706592708336298669839281 0 (mod 3)
30 : 8282112896813706592708336298669839281
steps up to 44171268783006435161111126926239142833 0 (mod 3)
31 : 44171268783006435161111126926239142833
steps up to 235580100176034320859259343606608761777 0 (mod 3)
32 : 235580100176034320859259343606608761777
steps up to 1256427200938849711249383165901913396145 0 (mod 3)
33 : 1256427200938849711249383165901913396145
steps up to 6700945071673865126663376884810204779441 1 (mod 3)
Nifty, eh?
That's as far as I've got.
>
> 1chains available formats : 2p + 1 = 1/2
> link function : 4p + 1
> link formats : 8i + 5 = 1/8
> proportion left : 1/2 - 1/8 = 3/8 of odd integers
> pivots : 4i + 3
> 8i + 1
> total 1/4 + 1/8 = 3/8
>
>
> 2chains available formats : 4i + 3
> 8i + 1 = 3/8
> link functions : 2p + 1
> 32p + 17
> link formats : 2(8i+1) + 1 = 16i + 3