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Forums: Index > Googology > Intro to BEAF review



I have been working hard on our Introduction to BEAF article, and it's coming along excellently. Any comments on the ordinal versions? I'm fairly convinced that legion arrays have BHO power, but I might be wrong. FB100Ztalkcontribs 23:41, December 6, 2013 (UTC)

BHO is only \(X\uparrow\uparrow X\text{&}X\text{&}n\). The limit is \(\psi(\Omega_\omega)\). Wythagoras (talk) 07:52, December 7, 2013 (UTC)

I believe you, but what's the proof of this? (Then again, I've only managed to prove \(\varepsilon_0 = X \uparrow\uparrow X\) myself.) FB100Ztalkcontribs 20:27, December 7, 2013 (UTC)
Anything? FB100Ztalkcontribs 22:03, December 9, 2013 (UTC)
Sorry for not responding earlier.
First, we shall prove \(X\uparrow\uparrow X2 = \varepsilon_1\).
We know that \(X\uparrow\uparrow X2 = lim(X\uparrow\uparrow X,(X\uparrow\uparrow X)^{X\uparrow\uparrow X},(X\uparrow\uparrow X)^{(X\uparrow\uparrow X)^{X\uparrow\uparrow X}}...)\) and \(\varepsilon_1 = lim(\varepsilon_0,\varepsilon_0^{\varepsilon_0},\varepsilon_0^{\varepsilon_0^{\varepsilon_0}}...)\).
Since \(\varepsilon_0 = X \uparrow\uparrow X\), \(\varepsilon_1 = X \uparrow\uparrow X2\). It is easy to extend this proof to \(\varepsilon_k = X \uparrow\uparrow X(k+1)\), and then proving that \(X\uparrow\uparrow\uparrow X = \zeta_0\) shouldn't be that hard too.
But after that, it gets somewhat complicated, but with a proof \(\{X,X,n+1\}\text{&}n=\varphi(n,0)\) I can do it. Wythagoras (talk) 06:27, December 10, 2013 (UTC)
Hold up. In the article, I defined \(\omega \uparrow\uparrow (\omega + 1) = \varepsilon_1\). Can you give me a reason why \(\omega \uparrow\uparrow \omega 2\) is better? FB100Ztalkcontribs 06:31, December 10, 2013 (UTC)
\(\omega\uparrow\uparrow(\omega+1)=\omega^{\omega\uparrow\uparrow\omega+1}=\omega^{\varepsilon_0+1}\). \(\omega\uparrow\uparrow(\omega+n)\) are given by adding more \(\omega\)'s, and in the limit they give \(\varepsilon_1=\omega \uparrow\uparrow \omega 2\). LittlePeng9 (talk) 14:34, December 10, 2013 (UTC)

Sorry for being stubborn, but I'm still not convinced. It seems that there are multiple interpretations of what arrow notation and BEAF does for transfinites — one is \(\varepsilon_1 = \omega \uparrow\uparrow (\omega + 1)\), and the other is \(\varepsilon_1 = \omega \uparrow\uparrow \omega 2\). FB100Ztalkcontribs 23:00, December 10, 2013 (UTC)

And by Saibian's variant, . By his definition, and unlike other notations, has exactly entries. Ikosarakt1 (talk ^ contribs) 20:34, July 14, 2014 (UTC)
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