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   Square Root, Floor, and Factorial
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   Author  Topic: Square Root, Floor, and Factorial  (Read 1626 times)
ThudnBlunder
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Square Root, Floor, and Factorial  
« on: Jan 5th, 2007, 10:00am »
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Express the numbers 4 to 9 as economically as possible using only one '3' and as many square root, floor, and (standard) factorial functions as you require. eg,  
1 requires 2 operations as 1 = floor(sqrt(3)) or FS3, for short.  
2 requires 3 operations as 2 = floor(sqrt(3!)) or FS(3!), for short.
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Re: Square Root, Floor, and Factorial  
« Reply #1 on: Jan 5th, 2007, 10:43am »
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Is the "standard" factorial of a non-integer well defined for this problem?  If not, I'm seeing:
 
4. FSSSSSS((FSSSSSSS(((FSS(3!!))!!))!) (23 operations)
5. FSS(3!!) (5 operations)
6. 3! (1 operation)
7. FSSSSSSSSSSS(3!!!) (15 operations)
8. FSS((FSSSSSSSSSSS(3!!!))!) (19 operations)
9. FSSSS((FSSSSSSSSS((FSSSS((FSSSSSSS((FSS(3!!))!!))!))!))!) (38 operations)
 
[edit] expanded references and added 9 from below [/edit]
 
--SMQ
« Last Edit: Jan 5th, 2007, 12:13pm by SMQ » IP Logged

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ThudnBlunder
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Re: Square Root, Floor, and Factorial  
« Reply #2 on: Jan 5th, 2007, 11:21am »
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on Jan 5th, 2007, 10:43am, SMQ wrote:
Is the "standard" factorial of a non-integer well defined for this problem?
--SMQ

Nope.
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Re: Square Root, Floor, and Factorial  
« Reply #3 on: Jan 5th, 2007, 12:10pm »
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9. FSSSS((FSSSSSSSSS((FSSSS((FSSSSSSS((FSS(3!!))!!))!))!))!) (38 operations)
 
--SMQ
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ThudnBlunder
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Re: Square Root, Floor, and Factorial  
« Reply #4 on: Apr 30th, 2007, 12:00pm »
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on Jan 5th, 2007, 12:10pm, SMQ wrote:
9. FSSSS((FSSSSSSSSS((FSSSS((FSSSSSSS((FSS(3!!))!!))!))!))!) (38 operations)
--SMQ

Can be done in 36
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