Four 4s
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- Kai Laddiman
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Four 4s
Yes, it's that puzzle that everyone has already done, it's Four 4s!
You have to use all four 4s to make every number from 1 to 100. Pretty simple.
You can use most functions; if they are dubious, ask about them.
Banned functions:
Integer brackets []
Trigonononononometric thingies sin cos tan etc.
Powers
Stuff like that.
First person to get 1 wins a signed VFSMB.
You have to use all four 4s to make every number from 1 to 100. Pretty simple.
You can use most functions; if they are dubious, ask about them.
Banned functions:
Integer brackets []
Trigonononononometric thingies sin cos tan etc.
Powers
Stuff like that.
First person to get 1 wins a signed VFSMB.
16/10/2007 - Episode 4460
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
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Re: Four 4s
Sorry; what is the significance of 'integer' brackets [] as opposed to ()?
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Re: Four 4s
Integer brackets ignore decimals, for example [sqrt(sqrt(4))] would be the integer of sqrt 2, ie. 1.Daniel O'Dowd wrote:Sorry; what is the significance of 'integer' brackets [] as opposed to ()?
16/10/2007 - Episode 4460
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
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Re: Four 4s
1 = (4/4)*(4/4)Kai Laddiman wrote:First person to get 1 wins a signed VFSMB.
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Re: Four 4s
2= (4/4)+(4/4)Matt Morrison wrote:1 = (4/4)*(4/4)Kai Laddiman wrote:First person to get 1 wins a signed VFSMB.
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Re: Four 4s
3= (4*4-4)/4Steve Durney wrote:2= (4/4)+(4/4)Matt Morrison wrote:1 = (4/4)*(4/4)Kai Laddiman wrote:First person to get 1 wins a signed VFSMB.
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Re: Four 4s
4 = 4
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Re: Four 4s
The rules say you need to use all four fours.Charlie Reams wrote:4 = 4
So (4-4)x4+4 = 4
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Re: Four 4s
You've used five 4s...Howard Somerset wrote:The rules say you need to use all four fours.Charlie Reams wrote:4 = 4
So (4-4)x4+4 = 4
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Re: Four 4s
You've used a 5.Michael Wallace wrote:You've used five 4s...Howard Somerset wrote:The rules say you need to use all four fours.Charlie Reams wrote:4 = 4
So (4-4)x4+4 = 4
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Re: Four 4s
No. I've used only four 4s. The fifth is the result.Michael Wallace wrote:You've used five 4s...Howard Somerset wrote:The rules say you need to use all four fours.Charlie Reams wrote:4 = 4
So (4-4)x4+4 = 4
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Re: Four 4s
It would seem my 'humour' is wasted hereHoward Somerset wrote:No. I've used only four 4s. The fifth is the result.
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Re: Four 4s
We'd have difficulty when we get to 44.Michael Wallace wrote:It would seem my 'humour' is wasted hereHoward Somerset wrote:No. I've used only four 4s. The fifth is the result.
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Re: Four 4s
Looking ahead a little:
Is sqrt allowed?
Is factorial allowed?
Is sqrt allowed?
Is factorial allowed?
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Re: Four 4s
May the fours be with you.
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Re: Four 4s
Am I allowed to go for the next one too?
If so, (4x4+4)/4 = 5
If so, (4x4+4)/4 = 5
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Re: Four 4s
((4 + 4) / 4) + 4 = 6
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Re: Four 4s
4 + 4 - 4/4 = 7
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Re: Four 4s
I'm not afraid to admit that 14 is stumping me.
A clear definition of which functions we can and can't use might help?
A clear definition of which functions we can and can't use might help?
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Re: Four 4s
If it's allowed, then 4 x 4 - 4 + sqrt(4) = 14Matt Morrison wrote:I'm not afraid to admit that 14 is stumping me.
A clear definition of which functions we can and can't use might help?
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Re: Four 4s
Cool. I'd avoided square roots, but they're officially in now. Thumbs up for factorials too.Howard Somerset wrote:If it's allowed, then 4 x 4 - 4 + sqrt(4) = 14Matt Morrison wrote:I'm not afraid to admit that 14 is stumping me.
A clear definition of which functions we can and can't use might help?
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Re: Four 4s
I'm sure that when I did this at school in 1953 we used sqrt and factorial. And I think it was somewhere in the 30s where we got stuck.
After allowing [], which Kai has outlawed, pretty well anything becomes possible.
We also used concatenation, which Kai needs to rule upon, e.g. 44 + 44 = 88
After allowing [], which Kai has outlawed, pretty well anything becomes possible.
We also used concatenation, which Kai needs to rule upon, e.g. 44 + 44 = 88
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Re: Four 4s
44 + 4-4 = 44Howard Somerset wrote:We'd have difficulty when we get to 44.Michael Wallace wrote:It would seem my 'humour' is wasted hereHoward Somerset wrote:No. I've used only four 4s. The fifth is the result.
GR MSL GNDT MSS NGVWL SRND NNLYC NNCT
Re: Four 4s
(4 + 4) * 4 / 4 = 8
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Re: Four 4s
4 + 4 + 4/4 = 9
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Re: Four 4s
(4-(4/4))! + 4 = 10
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Re: Four 4s
4 x 4 - sqrt(4 x 4) = 12
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Re: Four 4s
(4!4+4!+4)/4=13
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Re: Four 4s
4!/4 + 4 + 4 = 14
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Re: Four 4s
Second 4 should be removed. Nice one.Jon O'Neill wrote:(4!4+4!+4)/4=13
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Re: Four 4s
4x4+4/4=17
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Re: Four 4s
(4!+4!+4)/4 without concatenationDaniel O'Dowd wrote:4!−(44/4)=13
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Re: Four 4s
4*4 +(4 /sqrt4 )=18 4!-4-(4/4)=19
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Re: Four 4s
4 x (4 + 4/4) = 20
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Re: Four 4s
I think that's what Jono was trying to say. He put an extra 4 in by mistake.Matt Morrison wrote:(4!+4!+4)/4 without concatenation
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Re: Four 4s
4!-4-4+4=20 4!-4 +(4/4)=21 4*4+4+sqrt4=22
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Re: Four 4s
You missed 18:
4!-Sq4-Sq4-Sq4=18
4!-Sq4-Sq4-Sq4=18
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Re: Four 4s
Daniel O'Dowd wrote:You missed 18:
4!-Sq4-Sq4-Sq4=18
Liam Tiernan wrote:4*4 +(4 /sqrt4 )=18
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Re: Four 4s
((4!*4)-4)/4=23
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Re: Four 4s
4! - 4/sqrt(4x4) = 23
4! x 4/sqrt(4x4) = 24
4! + 4/sqrt(4x4) = 25
4! x 4/sqrt(4x4) = 24
4! + 4/sqrt(4x4) = 25
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Re: Four 4s
(44+4)/sqrt4=24
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Re: Four 4s
((44/4)*sqrt4)+4=26
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Re: Four 4s
4!+4-(4/4)=27
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Re: Four 4s
4!+4+4-4=28 4!+4+(4/4)=29 4!+4+(4/sqrt4)=30
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Re: Four 4s
Yup and yup.Howard Somerset wrote:Looking ahead a little:
Is sqrt allowed?
Is factorial allowed?
16/10/2007 - Episode 4460
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
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Re: Four 4s
OK then, the following functions are allowed:
sqrt
factorial ! (sorry Charlie) and any variants of it
concatenation (although it is possible to get them all without it )
And, yeh, I think that's it. And by factorial variations, well, Wikipedia!
sqrt
factorial ! (sorry Charlie) and any variants of it
concatenation (although it is possible to get them all without it )
And, yeh, I think that's it. And by factorial variations, well, Wikipedia!
16/10/2007 - Episode 4460
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
- Kai Laddiman
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Re: Four 4s
Er, I'm having trouble keeping up with all of these solutions (I sleep), but I think we've got all of the ones up to 30, no?
16/10/2007 - Episode 4460
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
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Re: Four 4s
Glad to hear that. I think this puzzle is made possible because sqrt(4) is an integer.Kai Laddiman wrote:Yup and yup.Howard Somerset wrote:Looking ahead a little:
Is sqrt allowed?
Is factorial allowed?
But I was concerned when you outlawed powers, because sqrt is simply a power of 0.5. Glad you've allowed this exception.
Good to see you didn't carry on too much further after I'd gone to bed. I was expecting to see many more done by this morning.Liam Tiernan wrote:4!+4+4-4=28 4!+4+(4/4)=29 4!+4+(4/sqrt4)=30
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Re: Four 4s
Another couple of questions:
Can we have decimal points? e.g. 4/.4 = 10
Can we have recurring decimals? e.g.
If so, then
Can we have decimal points? e.g. 4/.4 = 10
Can we have recurring decimals? e.g.
Code: Select all
.
4/.4 = 9
Code: Select all
.
4! + 4/.4 - sqrt(4) = 31
Last edited by Howard Somerset on Sun Jun 14, 2009 8:56 am, edited 1 time in total.
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Re: Four 4s
Thanks Howard. Drunk.Howard Somerset wrote:I think that's what Jono was trying to say. He put an extra 4 in by mistake.Matt Morrison wrote:(4!+4!+4)/4 without concatenation
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Re: Four 4s
Er, if you absolutely have to, then use decimal points. Although it's possible without them...Howard Somerset wrote:Another couple of questions:
Can we have decimal points? e.g. 4/.4 = 10
Can we have recurring decimals? e.g.If so, thenCode: Select all
. 4/.4 = 9
Code: Select all
. 4! + 4/.4 - sqrt(4) = 31
16/10/2007 - Episode 4460
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
Dinos Sfyris 76 - 78 Dorian Lidell
Proof that even idiots can get well and truly mainwheeled.
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Re: Four 4s
YW. Guessed so.Jon O'Neill wrote:Thanks Howard. Drunk.Howard Somerset wrote:I think that's what Jono was trying to say. He put an extra 4 in by mistake.Matt Morrison wrote:(4!+4!+4)/4 without concatenation
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Re: Four 4s
We were given this at school to occupy us for half an hour while our teacher did his pools. I got stuck at (I think) 33. Years later, lying on a beach, I suddenly thought "Decimals! And recurring decimals!!" (I have good holidays.)
After that I had another bash and kept a dog-eared piece of paper with all I could get up to about 500. I'm proud to say that when I discovered the internet I'd got every single one that's possible without using gamma functions and natural logarithms.
After that I had another bash and kept a dog-eared piece of paper with all I could get up to about 500. I'm proud to say that when I discovered the internet I'd got every single one that's possible without using gamma functions and natural logarithms.
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Re: Four 4s
Next one's easy (4*4)+(4*4)=32
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Re: Four 4s
Apologies Jono, didn't notice yours was for 13 too, not trying to steal your thunder!
But yeah if Kai says it can be done without concatenation and decimals, let's do it without. I'm still stuck on 31.
But yeah if Kai says it can be done without concatenation and decimals, let's do it without. I'm still stuck on 31.
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Re: Four 4s
Next one..........not so easy.