Actual formulas for tetration and its derivative
#10
andydude Wrote:
hyper4geek Wrote:TetraExp[x] == TetraExpPrime[x] / TetraExpPrime[x-1]
TetraExp[x] == ProductLog[TetraExpPrime[x+1] / TetraExpPrime[x-1]]

But until I can derive the second formula, I'll assume that it's magic Smile

Its quite easily derived Tongue
\( \text{TetraExpPrime}[x+1] / \text{TetraExpPrime}[x-1]=\left({}^{x+1}e\right)\left( {}^x e\right)=\left(e^{{}^x e}\right)\left({}^xe\right) \) by the first formula.
But W is the inverse function of \( xe^x \) so \( W(ye^y)=y \), then let \( y={}^xe \) and you have it.

PS: Thanks a lot for this seminar presentation. *Always wonders where from Andrew gets his information*
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Messages In This Thread
RE: Actual formulas for tetration and its derivative - by bo198214 - 08/31/2007, 07:28 PM

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