Googology Wiki
Advertisement
Googology Wiki

Hyp cos Hyp cos 11 January 2018
1

Monotonic FS systems

I don't know how you understand "a monotonic FS system", but in this blog post, I'll use "monotonic" for some special FS systems.

Definition 1: In a fundamental sequence system \(S:\mu\cap\text{Lim}\times\mathbb N\rightarrow\mu\), let \(\lambda\alpha\ge0\).

  1. If \(\beta\) is a successor ordinal, then let \(\beta=\gamma+1=\lambda[n_1]_S[n_2]_S\cdots[n_k]_S[]_S\) where \(n_k>0\) (\(k\ge0\)). \(\alpha
Read Full Post
Hyp cos Hyp cos 21 October 2017
1

Are these functions well-defined?

Here are two extensions of subcubic graph function, but I don't know whether they are well-defined.


Graph A is called a graph minor of graph B if A can be obtained from B by these 3 operations:

  1. Delete an edge;
  2. Delete an isolated vertex;
  3. Edge contraction - for an edge ab, delete this edge, and replace vertex a and b by one vertex connecting to the edges which a or b formerly connect to. (If a and b are linked by another edge, it will become a self-loop after edge contraction.)

Graph A is called a topological minor of graph B if A can be obtained from B by these 3 operations:

  1. Delete an edge;
  2. Delete an isolated vertex;
  3. Smoothing - for a (degree=2) vertex a which links to b and c, delete vertex a, and replace edge ab and ac by one edge bc.

For (unlabeled) subcubic graphs, graph m…


Read Full Post
Hyp cos Hyp cos 2 October 2017
3

General fundamental sequences for OCFs

In definitions of some ordinal collapsing functions (OCFs), there is always a series of \(C_n(\text{some arguments})\) sets. \(C_0(\text{something})\) may contains some argument in the "something", and may contains a "large" ordinal for collapsing; \(C_{n+1}(\text{something})\) is usually obtained from \(C_n(\text{something})\) by applying some operations with some limitations (avoiding "loop" definition); and \(C(\text{something})\) is the union of all \(C_n(\text{something})\). By this structure, we can define general fundamental sequences for OCFs.


Here this "general" definition works on the notation using a weakly compact cardinal. The definition of the ordinal notation is:

Let \(K\) denote the weakly compact cardinal, \(\Omega_0=0\) and…


Read Full Post
Hyp cos Hyp cos 14 September 2017
6

Advanced approximation project

Current approximations can be further improved, and this will take large amount of edits, so I start this discussion.


BEAF is not well-defined beyond tetrational arrays. More accurately, \(X\uparrow\uparrow A\&n\) where \(A\) is not a single number (e.g. \(X+1\), \(2X\), \(X^2\), \(X^X\), etc.) and beyond are not well-defined. But \(X\uparrow\uparrow m\&n\) and \(X\uparrow\uparrow X\&n\) are still considered as well-defined.

My suggestion about that is:

  1. Approximations of numbers defined in ill-defined BEAF should be removed.
  2. Approximations in ill-defined BEAF of any numbers should be removed.
Read Full Post
Hyp cos Hyp cos 13 July 2017
1

Growth Rate ε(0)−1

What's the growth rate of Goodstein function? \(\varepsilon_0\)?

No. Unlike Hydra function and Worm function, which are comparable to \(f_{\varepsilon_0}(n)\), Goodstein function has some "cost" - \(G(2\uparrow\uparrow n)\approx f_{\varepsilon_0}(n)\). By the definition of "functional approximation":

\(f\ge^*g\) if there exists k such that for all n > 0, \(f(n+k)\ge g(n)\)

and

\(f\approx g\) if \(f\ge^*g\) and \(g\ge^*f\)

Goodstein function is not comparable to \(f_{\varepsilon_0}(n)\). Currently we don't have a compact notation to express the growth rate of it. However, in this blog post I won't consider this thing. Instead, I'll consider what it "costs" and extend it. Goodstein has a 3-level cost under \(\varepsilon_0\), since \(G(f_3(n))\app…

Read Full Post

Advertisement