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### Ordinals in googology

Posted: **September 26th, 2019, 7:12 am**

by **testitemqlstudop**

...This topic is taking over BOTH the LTCFC and TFNCAQ so now it deserves its own thread.

Primarily I'm concerned about large ordinals here.

For example, the first fixed point of ∂ |-> w∂ is w^^2. Hence we can make a function:

f(i) = the i-th fixed point of ∂ |-> w∂

What would f(2) be? f(w)? Would the last fixed point of ∂ |-> w∂ be well-defined?

At this point there is a function that diagonalizes from epsilon 0:

f(i) =the 1st fixed point of ∂ |-> {w, ∂, i, 1}

...if I got BEAF correct.

Then we effectively get a new fast growing function t(i), where assuming FGH is the fgh function,

t(i) = FGH_f(i)(2)

### Re: Ordinals

Posted: **September 26th, 2019, 7:20 am**

by **Moosey**

testitemqlstudop wrote:...This topic is taking over BOTH the LTCFC and TFNCAQ so now it deserves its own thread.

Primarily I'm concerned about large ordinals here.

For example, the first fixed point of ∂ |-> w∂ is w^^2. Hence we can make a function:

f(i) = the i-th fixed point of ∂ |-> w∂

What would f(2) be? f(w)? Would the last fixed point of ∂ |-> w∂ be well-defined?

At this point there is a function that diagonalizes from epsilon 0:

f(i) =the 1st fixed point of ∂ |-> {w, ∂, i, 1}

...if I got BEAF correct.

Then we effectively get a new fast growing function t(i), where assuming FGH is the fgh function,

t(i) = FGH_f(i)(2)

I believe that f(2) would be w^w^w judging by the fact that e_1 = e_0^^w

EDIT:

it's probably a good idea to mention my

ord function up here.

Formal definition:

oddpart(n)=

Code: Select all

```
oddpart(n/2), n/2 ∈ natural numbers
n, n/2 ∈ not-natural numbers
```

twoeypart(n)=

ord(n)=

Code: Select all

```
(ord(log_2(twoeypart(n))),ord((oddpart(n)-1)/2)), n>0
0, n=0
```

### Re: Ordinals

Posted: **September 26th, 2019, 7:24 am**

by **testitemqlstudop**

Which f

### Re: Ordinals

Posted: **September 26th, 2019, 3:51 pm**

by **Moosey**

testitemqlstudop wrote:Which f

the first one

EDIT:

I think it's worth mentioning the (informal) definitions of

fundamental sequences, the fgh, and

a crappy hierarchy I came up with.

The fgh, sgh, and HH are all defined in the general format

f_n(x) =

Code: Select all

```
x, n = 0
f_n[x](x), n a lim ord
[something involving f_n-1(x)] otherwise
```

for instance, the fgh is:

f_n(x) =

Code: Select all

```
x+1, n = 0
f_n[x](x), n a lim ord
f^x_n-1(x) otherwise
```

and the HH is:

h_n(x) =

Code: Select all

```
x, n = 0
h_n[x](x), n a lim ord
h_n-1(x+1) otherwise
```

Which is surprisingly totally different and much more faster than the sgh:

g_n(x)=

Code: Select all

```
x, n = 0
g_n[x](x), n a lim ord
g_n-1(x)+1 otherwise
```

About your second f:

testitempimplesquidIDyoulot wrote:f(i) =the 1st fixed point of ∂ |-> {w, ∂, i, 1}

...if I got BEAF correct.

f(1) > gamma_0 (which is {w,w,1,1}. The reader could refer to the bottom of

this section for ordinal beaf.) since it is a |-> {w, a, 1, 1}

Here's something which grows faster than t(i)

tmod(i) = fgh_f(i)(i)

Which is just t but it's of I rather than 2, making it larger for large values

### Re: Ordinals

Posted: **September 27th, 2019, 1:07 am**

by **Hdjensofjfnen**

I've posted the **fifth** post in this thread.

### Re: Ordinals

Posted: **September 27th, 2019, 3:08 am**

by **testitemqlstudop**

Ok screw it that's not what I mean

### Re: Ordinals

Posted: **September 27th, 2019, 6:34 am**

by **Moosey**

Hdjensofjfnen wrote:I've posted the **fifth** post in this thread.

Well done

Hopefully we can get to w posts soon...

(For those who are itching to make a lot of posts, please don't. Go to random posts or somewhere else)

### Re: Ordinals in googology

Posted: **September 27th, 2019, 6:45 am**

by **Moosey**

Here's what one could call the

hardy, fast and slow-growing hierarchy:

hsf_n(x)=

Code: Select all

```
x, n = 0
hsf_n[x](x), n a lim ord
hsf^x_n-1(x+1)+1 otherwise
```

More fgh variants:

f(x) =

Code: Select all

```
x+1, n = 0
f_n[f_n[x](x)](x), n a lim ord
f^x_n-1(x) otherwise
```

(Grows significantly faster than the normal fgh)

f(x) =

Code: Select all

```
x+1, n = 0
f_g(x,n,x)(x), n a lim ord
f^x_n-1(x) otherwise
define g(m,n,x) =
n[f_g(m-1,n,x)(x)], m>0,
x, m less than or = to 0
```

(An extension of the previous)

Or something similar:

f(x) =

Code: Select all

```
x+1, n = 0
f_g(x,n,x)(x), n a lim ord
f^x_n-1(x) otherwise
define g(m,n,x) =
n[g(m-1,n,x)], m>0,
x, m less than or = to 0
(g is just n[n[n[n[n[n[n[....x]]]]], with m ns)
```

Which is probably less powerful but sill pretty simple and much more powerful than the fgh (for inputs >= w2, since w[n] = n)

### Re: Ordinals in googology

Posted: **September 27th, 2019, 7:47 am**

by **testitemqlstudop**

Congratulations, we now need an fgh for the fgh.

### Re: Ordinals in googology

Posted: **September 27th, 2019, 8:39 am**

by **Moosey**

testitemqlstudop wrote:Congratulations, we now need an fgh for the fgh.

Nah, we can approximate values in what I'll call the weak moose-growing hierarchy

wm_n(x)=

Code: Select all

```
x+1, n = 0
wm_g(x,n,x)(x), n a lim ord
wm^x_n-1(x) otherwise
define g(m,n,x) =
n[g(m-1,n,x)], m>0,
x, m less than or = to 0
(g is just n[n[n[n[n[n[n[....x]]]]], with m ns)
```

<late edit>oh crumbs, wm isn't defined for a lot of ordinals when you get to stuff like n[w^w]</late edit>

And strong moose-growing hierarchy:

sm_n(x)=

Code: Select all

```
x+1, n = 0
sm_g(x,n,x)(x), n a lim ord
sm^x_n-1(x) otherwise
define g(m,n,x) =
n[sm_g(m-1,n,x)(x)], m>0,
x, m less than or = to 0
```

In terms of the fgh

What is sm_w(n) in the fgh?

(Note to self: remember to add a link to this (

viewtopic.php?f=12&t=4131&p=83326#p83326) with a name like "sm and wm" to the fluffykitty conwaylife googology googology wiki page; I'm at school and they block wikia so I can't do it right now.)

### Re: Ordinals in googology

Posted: **September 27th, 2019, 9:41 am**

by **BlinkerSpawn**

testitemqlstudop wrote:...This topic is taking over BOTH the LTCFC and TFNCAQ so now it deserves its own thread.

Primarily I'm concerned about large ordinals here.

For example, the first fixed point of ∂ |-> w∂ is w^w. Hence we can make a function:

f(i) = the i-th fixed point of ∂ |-> w∂

What would f(2) be? f(w)? Would the last fixed point of ∂ |-> w∂ be well-defined?

∂ |-> w∂ is the same as w^∂ |-> w^(1+∂), so f(i) is w^{i'th limit of successors} = w^(wi). The "last fixed point" does not exist because there is no greatest ordinal.

### Re: Ordinals

Posted: **September 27th, 2019, 10:20 am**

by **PkmnQ**

Moosey wrote:
The fgh, sgh, and HH are all defined in the general format

f_n(x) =

Code: Select all

```
x, n = 0
f_n[x](x), n a lim ord
[something involving f_n-1(x)] otherwise
```

What if I...

Ę_m_n(x) =

Code: Select all

```
x, m=0 and n=0
Ę_m_n[x](x), n a limit ord
Ę_m_n-1(x+1) n not a limit ord
Ę_m[x]_m(x), n=0 and m a limit ord
Ę_m-1_m(x+1), n=0 and m not a limit ord
```

Code: Select all

```
Ę_w_w(1)
Ę_w_1(1)
Ę_w_0(2)
Ę_2_w(2)
Ę_2_2(2)
Ę_2_1(3)
Ę_2_0(4)
Ę_1_2(5)
Ę_1_1(6)
Ę_1_0(7)
Ę_0_1(8)
Ę_0_0(9)
9
```

Code: Select all

```
Ę_w_w^2+1(2)
Ę_w_w^2(3)
Ę_w_w3(3)
Ę_w_9(3)
Ę_w_0(12)
Ę_12_w(12)
Ę_12_12(12)
Ę_12_0(24)
Ę_11_12(25)
Ę_11_0(37)
Ę_10_11(38)
Ę_10_0(49)
Ę_9_10(50)
Ę_9_0(60)
Ę_8_9(61)
Ę_8_0(70)
Ę_7_8(71)
Ę_7_0(79)
Ę_6_7(80)
Ę_6_0(87)
Ę_5_6(88)
Ę_5_0(94)
Ę_4_5(95)
Ę_4_0(100)
Ę_3_4(101)
Ę_3_0(105)
Ę_2_3(106)
Ę_2_0(109)
Ę_1_2(110)
Ę_1_0(112)
Ę_0_1(113)
Ę_0_0(114)
114
```

### Re: Ordinals in googology

Posted: **September 27th, 2019, 8:10 pm**

by **testitemqlstudop**

Any limit ordinal ∂ is the supremum of all elements in its fundamental sequence?

### Re: Ordinals in googology

Posted: **September 28th, 2019, 2:18 am**

by **testitemqlstudop**

BlinkerSpawn wrote:

∂ |-> w∂ is the same as w^∂ |-> w^(1+∂), so f(i) is w^{i'th limit of successors} = w^(wi). The "last fixed point" does not exist because there is no greatest ordinal.

There has to be something wrong with that logic, because if ∂ = w2 = w+w, then it is implied that w+w = w(w+w), or w+w = w^2+w^2.

### Re: Ordinals in googology

Posted: **September 28th, 2019, 7:05 am**

by **Moosey**

testitemqlstudop wrote:BlinkerSpawn wrote:

∂ |-> w∂ is the same as w^∂ |-> w^(1+∂), so f(i) is w^{i'th limit of successors} = w^(wi). The "last fixed point" does not exist because there is no greatest ordinal.

There has to be something wrong with that logic, because if ∂ = w2 = w+w, then it is implied that w+w = w(w+w), or w+w = w^2+w^2.

You can't just assign arbitrary values unless you follow the such that.

Of course it won't work for ∂ = w2

testitemqlstudop wrote:Any limit ordinal ∂ is the supremum of all elements in its fundamental sequence?

By definition,

yes.

### Re: Ordinals in googology

Posted: **September 30th, 2019, 4:43 pm**

by **BlinkerSpawn**

testitemqlstudop wrote:BlinkerSpawn wrote:

∂ |-> w∂ is the same as w^∂ |-> w^(1+∂), so f(i) is w^{i'th limit of successors} = w^(wi). The "last fixed point" does not exist because there is no greatest ordinal.

There has to be something wrong with that logic, because if ∂ = w2 = w+w, then it is implied that w+w = w(w+w), or w+w = w^2+w^2.

Of course w2 doesn't work, it's not of form w^(wa).

### Re: Ordinals in googology

Posted: **September 30th, 2019, 4:51 pm**

by **Moosey**

BlinkerSpawn wrote:testitemqlstudop wrote:BlinkerSpawn wrote:

∂ |-> w∂ is the same as w^∂ |-> w^(1+∂), so f(i) is w^{i'th limit of successors} = w^(wi). The "last fixed point" does not exist because there is no greatest ordinal.

There has to be something wrong with that logic, because if ∂ = w2 = w+w, then it is implied that w+w = w(w+w), or w+w = w^2+w^2.

Of course w2 doesn't work, it's not of form w^(wa).

Moosey wrote:testitemqlstudop wrote:BlinkerSpawn wrote:

∂ |-> w∂ is the same as w^∂ |-> w^(1+∂), so f(i) is w^{i'th limit of successors} = w^(wi). The "last fixed point" does not exist because there is no greatest ordinal.

There has to be something wrong with that logic, because if ∂ = w2 = w+w, then it is implied that w+w = w(w+w), or w+w = w^2+w^2.

You can't just assign arbitrary values unless you follow the such that.

Of course it won't work for ∂ = w2

### Re: Ordinals in googology

Posted: **October 3rd, 2019, 4:55 pm**

by **Moosey**

Does this notation I created do what I want?

It's sm but the g analogue preserves iteration

Code: Select all

```
ssm_n(x,y)=
x+y, n = 0
ssm_sg(x,n,x,y)(x,y), n a lim ord
ssm_n-1(x,xy) otherwise
define sg(m,n,x,y) =
n[ssm_sg(m-1,n,x)(x,y)], m>0,
x, m less than or = to 0
```

Remember:

Code: Select all

```
sm_n(x)=
x+1, n = 0
sm_g(x,n,x)(x), n a lim ord
sm^x_n-1(x) otherwise
define g(m,n,x) =
n[sm_g(m-1,n,x)(x)], m>0,
x, m less than or = to 0
```

Speaking of which, I should demonstrate the awesome power of sm:

sm_w(3)=

Code: Select all

```
sm_g(3,w,3)(3)=
sm_w[sm_g(2,w,3)(3)](3)=
sm_w[sm_w[sm_g(1,w,3)(3)](3)](3)=
sm_w[sm_w[sm_w[sm_g(0,w,3)(3)](3)](3)=
sm_w[sm_w[sm_w[sm_3(3)](3)](3)=
f_(f_(f_(f_3(3))(3))(3))(3))
f_3(3)= f_2(f_2(f_2(3)))
f_2(3)=(2^3)*3 = 24
f_3(3) = f_2(f_2(24)) =
f_2((2^24)*24) =
f_2(402653184) =
(2^402653184)*402653184
f_(f_(f_(f_3(3))(3))(3))(3)) =
f_(f_(f_(2^402653184)*402653184(3))(3))(3)) ...
>f_(f_(2{2^402653184*402653184-1}3)(3))(3))... (using bowers' notation)
> 2{2{2{2^402653184*402653184-1}3-1}3-1}3
```

So yeah...

Code: Select all

```
#C the 3-1's aren't twos -- you have to follow order of operations.
#C presumably more knuth arrows = higher priority in order of operations, but the point is that you're subtracting from the 2{huge thing}3 mess
x = 167, y = 24, rule = B/S012345678
63bobob3ob3ob3ob3ob3obob3obobo$63bobobobo3bobo3bo5bobobobobobo$63b3obo
bob3ob3ob3ob3obob3ob3o$65bobobobo3bobo3bo3bobobobo3bo$65bob3ob3ob3ob3o
b3obob3o3bo$59b3o39bobob3ob3ob3ob3ob3obob3obobo5bo$61bo39bobobobo3bobo
3bo5bobobobobobo5bo$59b3o35bobob3obobob3ob3ob3ob3obob3ob3ob3obo$59bo
38bo4bobobobo3bobo3bo3bobobobo3bo5bo$51b3o2bo2b3o35bobo3bob3ob3ob3ob3o
b3obob3o3bo5bo2b3o5bo$53bob3o86bo5bo$51b3o2bo85b3ob3obo$51bo4bo87bo5bo
$43b3o2bo2b3o2bo85b3o5bo2b3o5bo$45bob3o105bo5bo$43b3o2bo104b3ob3obo$
25b2o16bo4bo106bo5bo$14bob3obo6b2o6b3o2bo2b3o2bo104b3o5bo2b3o$b2o2b2o
6bo4bo2bo7bo7bob3o124bo$bo2b2o7bo2b3o2bo5b2o6b3o2bo123b3o$2o2bo3bobo2b
o4bo2bo3b2o8bo4bo125bo$7bo3bo2bob3obo14b3o2bo123b3o$7bobobo13b5o$8b3o!
```

while f_w(3) = (2^402653184)*402653184. When you have limit ordinals, sm becomes much much

*much* more powerful than the fgh, even though it behaves the same for finite numbers

PkmnQ wrote: ↑September 27th, 2019, 10:20 am

Moosey wrote:
The fgh, sgh, and HH are all defined in the general format

f_n(x) =

Code: Select all

```
x, n = 0
f_n[x](x), n a lim ord
[something involving f_n-1(x)] otherwise
```

What if I...

Ę_m_n(x) =

Code: Select all

```
x, m=0 and n=0
Ę_m_n[x](x), n a limit ord
Ę_m_n-1(x+1) n not a limit ord
Ę_m[x]_m(x), n=0 and m a limit ord
Ę_m-1_m(x+1), n=0 and m not a limit ord
```

Well done

Here's a stronger sm analogue:

smĘ_m_n(x)=

Code: Select all

```
x+1, m=0 and n=0
smĘ_m_ge(x,n,x)(x), n a lim ord
smĘ^x_m_n-1(x), n not a lim ord
smĘ_ge(x,m,x)_m(x), n=0 and m a lim ord
smĘ_m-1_m(x+1), n=0 and m not a lim ord
define ge(m,n,x) =
n[smĘ_ge(m-1,n,x)(x)], m>0,
x, m less than or = to 0
```

You could call it the "hardy strong-moose Ę hierarchy"

### Re: Ordinals in googology

Posted: **October 4th, 2019, 3:03 pm**

by **Moosey**

Anyone care to evaluate

smĘ_w_w(1)?

### Re: Ordinals in googology

Posted: **October 4th, 2019, 6:31 pm**

by **Moosey**

Here's a new thing

The decord (

**dec**reasing

**ord**inal) sequence:

start with an ordinal c as term 1.

Rules:

Iff term n is 0: stop

Else:

Iff term n (call it a) is a limit ord, whose minimum "term" (eg. in w^w + w^4 + w2 = w^w + w^4 + w + w, the minimum term is w) is b, and for whom the rest of the terms of a are called r:

term n+1 = r+b[n] + b[n-1] + b[n-2] ... b[1],

Else:

Term n+1 = a-1

Demo:

Code: Select all

```
w^w+1
w^w
w^2+w
w^2+6
w^2+5
w^2+4
w^2+3
w^2+2
w^2+1
w^2 (10th term)
w55
w54+66
...
w54 (78th term)
w53+3081
...
w53 (3160th term)
...
```

Obviously this leads to a new function:

the term in the decord sequence for the ordinal a at which it becomes zero = dco(a) (

**d**e

**co**rd)

dco(w+1) = 6, and dco(w^w+1) is ~tri^53(3160), give or take an iteration or two, where tri(n) = the nth triangular number. This suggests a reasonable bound of dco(w^w+1) << 3160^106 (though not in a googolplex-vs-g_64 kind of <<)

Since a[n] < a for all finite n, all decord sequences strictly decrease over time. Thus, dco(a) is finite for all a

### Re: Ordinals in googology

Posted: **October 4th, 2019, 8:51 pm**

by **PkmnQ**

Moosey wrote: ↑October 4th, 2019, 3:03 pm

Anyone care to evaluate

smĘ_w_w(1)?

I will, after I see what I can do with

Moosey wrote: ↑October 4th, 2019, 6:31 pm

Here's a new thing

The decord (

**dec**reasing

**ord**inal) sequence:

start with an ordinal c as term 1.

Rules:

Iff term n is 0: stop

Else:

Iff term n (call it a) is a limit ord, whose minimum "term" (eg. in w^w + w^4 + w2 = w^w + w^4 + w + w, the minimum term is w) is b, and for whom the rest of the terms of a are called r:

term n+1 = r+b[n] + b[n-1] + b[n-2] ... b[1],

Else:

Term n+1 = a-1

Demo:

Code: Select all

```
w^w+1
w^w
w^2+w
w^2+6
w^2+5
w^2+4
w^2+3
w^2+2
w^2+1
w^2 (10th term)
w55
w54+66
...
w54 (78th term)
w53+3081
...
w53 (3160th term)
...
```

Obviously this leads to a new function:

the term in the decord sequence for the ordinal a at which it becomes zero = dco(a) (

**d**e

**co**rd)

dco(w+1) = 6, and dco(w^w+1) is ~tri^53(3160), give or take an iteration or two, where tri(n) = the nth triangular number. This suggests a reasonable bound of dco(w^w+1) << 3160^106 (though not in a googolplex-vs-g_64 kind of <<)

Since a[n] < a for all finite n, all decord sequences strictly decrease over time. Thus, dco(a) is finite for all a

### Re: Ordinals in googology

Posted: **October 4th, 2019, 9:10 pm**

by **PkmnQ**

Here’s what I see about dco(n) right now.

₩(w) = 0

₩(w+1) = 1

₩(w^2+14233221) = 14233221

n < w dco(n) = n+1

w < n < w2 dco(n) = 2₩(n+1)+1

### Re: Ordinals in googology

Posted: **October 4th, 2019, 9:15 pm**

by **PkmnQ**

Moosey wrote: ↑October 3rd, 2019, 4:55 pm

smĘ_m_n(x)= (m and n)

Code: Select all

```
x+1, m=0 and n=0
smĘ_m_ge(x,n,x)(x), n a lim ord
smĘ^x_m_n-1(x), n not a lim ord
smĘ_ge(x,m,x)_m(x), n=0 and m a lim ord
smĘ_m-1_m(x+1), n=0 and m not a lim ord
define ge(m,n,x) =
n[smĘ_ge(m-1,n,x)(x)], m>0, (you only provided m)
x, m less than or = to 0
```

You could call it the "hardy strong-moose Ę hierarchy"

### Re: Ordinals in googology

Posted: **October 5th, 2019, 9:11 am**

by **Moosey**

PkmnQ wrote: ↑October 4th, 2019, 9:10 pm

Here’s what I see about dco(n) right now.

₩(w) = 0

₩(w+1) = 1

₩(w^2+14233221) = 14233221

n < w dco(n) = n+1

w < n < w2 dco(n) = 2₩(n+1)+1

what is the definition of ₩?

### Re: Ordinals in googology

Posted: **October 5th, 2019, 10:17 pm**

by **PkmnQ**

Moosey wrote: ↑October 5th, 2019, 9:11 am

PkmnQ wrote: ↑October 4th, 2019, 9:10 pm

Here’s what I see about dco(n) right now.

n < w dco(n) = n+1

w < n < w2 dco(n) = 2₩(n+1)+1

what is the definition of ₩?

I don’t reslly know how to give a definition, so that’s why I put

₩(w) = 0

₩(w+1) = 1

₩(w^2+14233221) = 14233221