Four 4s

Cerebral distractions of every kind, mostly but not exclusively Countdown-related.

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James Hall
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Re: Four 4s

Post by James Hall »

Neil Zussman wrote:Also, is my way of making 3 from two 4's by using infinitely many square roots (posted earlier) legal?
Normally you're only allowed a finite number of functions.

Kai, the gamma function, as far as integers are concerned, is defined thus:
Γ(n) = (n-1)!
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Neil Zussman
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Re: Four 4s

Post by Neil Zussman »

Presumably Kai means we can use double factorial. Thus 4!!=8 and ((4!!)!!)/4=96.
This means 3=4!/4!!, i.e. 3 can be made using just two 4's. Thus 51, 45, 93 and 99 can now be made (see my previous post). I'm sure lots more numbers can be made as well, although interest in the puzzle seems to have waned.
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Robert Baxter
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Re: Four 4s

Post by Robert Baxter »

33:

(4*4*sqrt 4)+sqrt 4
4!+(4!/4)+4
sqrt(4^4)*sqrt 4+sqrt 4

Edit: Told you I was an :ugeek:
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Re: Four 4s

Post by Kai Laddiman »

Robert Baxter wrote:33:

(4*4*sqrt 4)+sqrt 4
4!+(4!/4)+4
sqrt(4^4)*sqrt 4+sqrt 4

Edit: Told you I was an :ugeek:
There's only 3 there, not 33. Typo perhaps?
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Robert Baxter
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Re: Four 4s

Post by Robert Baxter »

Kai Laddiman wrote:
Robert Baxter wrote:33:

(4*4*sqrt 4)+sqrt 4
*4!+(4!/4)+4
sqrt(4^4)*sqrt 4+sqrt 4

Edit: Told you I was an :ugeek:
There's only 3 there, not 33. Typo perhaps?
Does this work?
Contestant: Continent please, Rachel.
Rachel: Y.
Contestant: Because I want one!

For more info, see http://wiki.apterous.org/User:The_Doctor , and don't have a go at me a the F1 drivers series.

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