Search found 213 matches

by Demki
Mon Aug 03, 2015 6:13 pm UTC
Forum: Coding
Topic: Esoteric programming languages for an esoteric mind?
Replies: 77
Views: 16007

Re: Esoteric programming languages for an esoteric mind?

What happens when you compile your code and run it? Re java.util.Scanner: what you are trying to do here is access a class provided by the library "java.util" which is named "Scanner". The compiler needs to know which library provides the code for "Scanner". You can ei...
by Demki
Sat Aug 01, 2015 11:52 am UTC
Forum: Mathematics
Topic: Conjecture "2^n"
Replies: 10
Views: 2609

Re: Conjecture "2^n"

Goahead52 wrote:Thank you for your proof.
You did not use Latex so I have big trouble understanding your formulas.
n could be prime so you could not write it your way n=2^w*3^...
I will take my time to decipher what you wrote.

If n is prime and not 2 or 3 then n=2^0 * 3^0 * d where d=n
by Demki
Wed Jul 29, 2015 8:10 pm UTC
Forum: Coding
Topic: Esoteric programming languages for an esoteric mind?
Replies: 77
Views: 16007

Re: Esoteric programming languages for an esoteric mind?

By what you wrote about static vs non-static methods I see you have a problem grasping basic concepts of object oriented programming, specifically class methods vs object methods. Class methods, labeled "static" are general methods specific to a class that do not require an instance of an ...
by Demki
Wed Jul 29, 2015 7:41 pm UTC
Forum: Mathematics
Topic: Prove that 25+8*(n!)) is not square
Replies: 10
Views: 3285

Re: Prove that 25+8*(n!)) is not square

lorb wrote:if n>=25 then 25+8*(n!) is always divisible by 25. So if it is a perfect square it has to be the square of a number divisible by 5.
(For n<25 we already know there are no squares by previous poster)

That's actually true for n>=10. Since 10! Is divisible by 25.
by Demki
Wed Jul 22, 2015 10:44 am UTC
Forum: Forum Games
Topic: Collatz Counting
Replies: 1154
Views: 51938

Re: Collatz Counting

185,339,500
by Demki
Sat Jul 11, 2015 4:31 pm UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

[是] [but] [네]
by Demki
Sat Jul 11, 2015 6:50 am UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

Guess: the sum of the numbers must be in the arithmetic sequence 4+5k (where k is an integer). If this is incorrect, then I guess that the sum must end in 4 or 9 (equivalent to the above only for positive integers). If I am not allowed to make two guesses then I will let someone else guess it. That...
by Demki
Fri Jul 10, 2015 8:52 pm UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

Demki: I resubmit the list of 1000 one-digit sequences I submitted to Vytron above. (And I ask that you label it correctly, as Vytron's failure to label [6][9][3] and friends totally threw me off last time.) This is gonna give away the rule quite quickly; the race to posting it begins... [0] [0] [0...
by Demki
Fri Jul 10, 2015 7:29 am UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

Vytron:
[64] [128] [256] NO

SirGabriel:
[1] [2] [3] NO
[1] [2] [4] NO
[32] [64] [256] NO
by Demki
Thu Jul 09, 2015 2:36 pm UTC
Forum: Forum Games
Topic: Fun Fact Trivia Time
Replies: 76
Views: 5474

Re: Fun Fact Trivia Time

...it originally served as a measure of fallen ham in South England beach picnics. Python's predecessor, ABC, was... Designed by preschool children, in an attempt to create a simple to learn language - they failed. Contrary to popular belief, people don't consume 8 glasses of water a day, they actu...
by Demki
Thu Jul 09, 2015 10:10 am UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

Vytron wrote:[128] [32] [64]
[64] [32] [128]
[64] [128] [32]
[32] [128] [64]

All of these obey the rule.
by Demki
Thu Jul 09, 2015 4:23 am UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

[3.2] [6.4] [12.8] NO
[3^2] [6^4] [12^8] NO
[thirty-two] [sixty-four] [one hundred twenty-eight] NO
[128] [64] [32] YES
[32] [64] [128] [256] NO
[32] [32] [32] NO
[-32] [-64] [-128] NO
[32] [64] [32] NO
[$32] [64¢] [€128] NO
[mouse] [rabbit] [whale] NO
by Demki
Wed Jul 08, 2015 8:28 pm UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

All right...

[32] [64] [128] obeys the rule
by Demki
Wed Jul 08, 2015 5:11 pm UTC
Forum: Mathematics
Topic: Wanted: Elegant proof of sin(x)/x limit
Replies: 49
Views: 8118

Re: Wanted: Elegant proof of sin(x)/x limit

Is the some reason we don't want to apply L'Hospital's rule? L'Hospital's rule requires the derivative of sin(x), which requires knowledge of this limit. Using L'H in this case is begging the question. Doh.. such a brain fart from me. How about using sin(x) series expansion? :P That, sadly(or not!)...
by Demki
Wed Jul 08, 2015 2:04 pm UTC
Forum: Forum Games
Topic: Guess The Rule
Replies: 44
Views: 2613

Re: Guess The Rule

[`] [``] [```] [`] [```] [``] [``] [```] [`] [```] [``] [`] [``] [```] [````] [`````] I'm gonna guess like this: If the first and last obey the rule: any sequence where the number of letters when written in english(2 becomes two) rises from left to right. If only the first obeys the rule: same as ab...
by Demki
Thu Oct 30, 2014 9:23 pm UTC
Forum: Mathematics
Topic: How many ways can you prove x + 1/x >= 2?
Replies: 23
Views: 14669

Re: How many ways can you prove x + 1/x >= 2?

I think I have a new one: All of the below assumes real x>0; We need to prove that x+1/x>=2; That's the same as x+1/x-2>=0; set f(x)=x+1/x-2; df/dx=1-1/x 2 ; d 2 f/dx 2 = 2/x^3; From this there's a critical point at x=1, and since the second derivative is greater than 0 it is a local minimum. Since ...
by Demki
Thu Aug 07, 2014 3:36 pm UTC
Forum: Mathematics
Topic: is mathematics a religion?
Replies: 82
Views: 14973

Re: is mathematics a religion?

Looking at your problem "Z is the greatest number and Y is the least, what is their sum?" A simple solution would be to use the natural numbers with the ordering B≤A if B divides A: 1 divides all numbers so it's the least, every number divides 0 so it's the greatest, so the sum is 1. There...
by Demki
Wed Mar 19, 2014 4:32 pm UTC
Forum: Logic Puzzles
Topic: The ambiguous clock
Replies: 4
Views: 3801

Re: The ambiguous clock

Been done before in this forum.Here it is.
by Demki
Fri Mar 14, 2014 6:05 am UTC
Forum: Logic Puzzles
Topic: Number substitution puzzle - multiplication
Replies: 21
Views: 6469

Re: Number substitution puzzle - multiplication

Finally the "solution" has come. It appears the intended puzzle was: -x- -x- ___ ---- ---- ---- ______ x---x- With the solution: 735 438 ___ 5880 2205 2940 ______ 321930 Probably a printing error, since on both of 2 newspapers I checked(2 weeks ago) the impossible version was given.(took a...
by Demki
Tue Mar 11, 2014 10:33 pm UTC
Forum: Mathematics
Topic: algebraic degree of sin(1 degree)
Replies: 4
Views: 2542

Re: algebraic degree of sin(1 degree)

I put sin(1 degree) in Wolfram|Alpha, found a form with only addition, multiplication and exponents, simplified it a bit, then put it back in Wolfram|Alpha to get: 281474976710656 x^48-3377699720527872 x^46+18999560927969280 x^44-66568831992070144 x^42+162828875980603392 x^40-295364007592722432 x^38...
by Demki
Tue Mar 11, 2014 1:47 pm UTC
Forum: Logic Puzzles
Topic: Number substitution puzzle - multiplication
Replies: 21
Views: 6469

Re: Number substitution puzzle - multiplication

Bloopy's solution is correct.
The reason I said a,b,d and g are not 0 is because I wrote
abc+def=ghi,abc-def=bdi
for instanec if b was 0, I'd have written abc-def=di. But since it doesn't change the uniqueness of the answer, it doesn't matter.
Well, now waiting for next week's paper.
by Demki
Fri Mar 07, 2014 10:51 pm UTC
Forum: Logic Puzzles
Topic: Number substitution puzzle - multiplication
Replies: 21
Views: 6469

Re: Number substitution puzzle - multiplication

I guess I should clear something up after looking at jedelmania's post: The variables(a,b,...,i) can be any number between 0 and 9. a,b,d,g can't be 0(the opperands and results are 3 digit numbers)
by Demki
Fri Mar 07, 2014 12:51 pm UTC
Forum: Logic Puzzles
Topic: Number substitution puzzle - multiplication
Replies: 21
Views: 6469

Re: Number substitution puzzle - multiplication

We draw ever closer to the "correct" answer... suspense is killing me. It appears I have misread the newspaper's dates in the solution section, since I have now noticed they give solution not to last week problems, but to the problem from 2 weeks ago. I am sorry, and I was killed by suspe...
by Demki
Fri Mar 07, 2014 10:58 am UTC
Forum: Mathematics
Topic: Axiomatic mathematics has no foundation
Replies: 158
Views: 32717

Re: Axiomatic mathematics has no foundation

These things are called sets. I mostly agree. In practice, it has been decided that a set can't contain itself... (at least in some set theories) which is one of those impossible fixed points. And I feel that sets themselves are a bit inefficient. But as a generic object that represents relationshi...
by Demki
Wed Mar 05, 2014 5:40 pm UTC
Forum: Logic Puzzles
Topic: The philosopher, the most intelligent man and the fish
Replies: 44
Views: 11751

Re: The philosopher, the most intelligent man and the fish

Let's try a deconstuction: In this street there is one car that appears green for colourblind people Colourblind people have no concept of colour, therefore have no concept of green, just a variation of grey. Yes, 98% ish of men are colourblind in the red/green spectrum to some degree, but this sta...
by Demki
Sat Mar 01, 2014 8:13 pm UTC
Forum: Logic Puzzles
Topic: Number substitution puzzle - multiplication
Replies: 21
Views: 6469

Re: Number substitution puzzle - multiplication

Interesting, couldn't find a fault in that.
Next Friday they will publish the answer, so we'll know for sure then.

I made a program to brute force it, and found no valid answerIt didn't check all possibilities, will probably try again tomorrow. Perhaps the newspaper was wrong.
by Demki
Sat Mar 01, 2014 5:38 pm UTC
Forum: Logic Puzzles
Topic: Number substitution puzzle - multiplication
Replies: 21
Views: 6469

Re: Number substitution puzzle - multiplication

I think I've just proven that no possible solution exists... Are you sure you copied the puzzle correctly? Yes, took a picture of the page, one '-' is not necessarily the same as another '-', and it's never equal to X. @Kingreaper To clear things up, It's like this: abc efg --- (g*abc) (f*abc) <thi...
by Demki
Sat Mar 01, 2014 1:41 pm UTC
Forum: Logic Puzzles
Topic: Number substitution puzzle - multiplication
Replies: 21
Views: 6469

Number substitution puzzle - multiplication

In the following multiplication a certain digit has been replaced by X, and other digits which aren't X by -, find the original digits and which digit doesn't appear. image.jpg Note: I don't have the correct answer yet, I'll have it by this time next week. It's from a local newspaper. If anyone know...
by Demki
Thu Feb 27, 2014 10:59 pm UTC
Forum: Mathematics
Topic: Easy Parabola problem
Replies: 17
Views: 3537

Re: Easy Parabola problem

Adam H wrote:Now make the transitions at y=0 smooth. :D

Just add f'(0)=f'(T)=0 to get a polynomial of degree 8.
by Demki
Sun Feb 23, 2014 5:11 pm UTC
Forum: Mathematics
Topic: What is the Chance(y)? Probability?
Replies: 4
Views: 1978

Re: What is the Chance(y)? Probability?

Let c = 0.039 and x = 1−0.45 = 0.55 c = odds of capture on first round cx = odds of capture on second round cx² = odds of capture on third round cx³ = odds of capture on fourth round You do the math. Weird, I got the following: c = odds of capture on the first round c(1-c)x = odds of capture on the...
by Demki
Mon Feb 17, 2014 3:06 pm UTC
Forum: Mathematics
Topic: Notation and properties of nested functions?
Replies: 19
Views: 3915

Re: Notation and properties of nested functions?

Another function that outputs the same:
f(x)=(x - ((-1)^x-1)(2.5x +1))/2

Though instead of quadratics, you get exponentiation.
by Demki
Fri Dec 13, 2013 10:48 pm UTC
Forum: Mathematics
Topic: Solving inequalities
Replies: 6
Views: 2300

Re: Solving inequalities

The way I learned to do these: (x 3 + 4)/(x - 1) > -4, x ≠ 1 Multiply by x-1. We're going to get two cases: if it's negative, the inequality flips. A) x 3 + 4 > -4(x - 1) = -4x + 4 and x > 1 (not equal to 1 because division by zero) or B) x 3 + 4 < -4(x - 1) = -4x + 4 and x < 1 A) x 3 + 4x > 0 and ...
by Demki
Wed Dec 11, 2013 4:23 pm UTC
Forum: Mathematics
Topic: condition for Det of order 2n =0
Replies: 5
Views: 1881

Re: condition for Det of order 2n =0

Is this homework?

Either way, what you got is definitely wrong, it should at least be an OR there, not AND.(for instance, (u,v,w,x)=(1,1,0,0) is a solution to the second equation and not the first one, yet the determinant of the resulting matrix is indeed 0).
by Demki
Mon Dec 09, 2013 4:05 pm UTC
Forum: Mathematics
Topic: Question about differential equations!
Replies: 5
Views: 2073

Re: Question about differential equations!

You probably made a slight mistake in posing the problem, because as it stands, lim x->oo v=0 and lim x->oo u=oo which means that automatically lim x->oo v 4 /u=0 You might've swapped the -4y' and 4y' or u and v Actually, lim x->oo u(x) is undefined because of the sin(x) part, the value of u fluctu...
by Demki
Wed Nov 27, 2013 10:04 pm UTC
Forum: Logic Puzzles
Topic: Misplaced Christmas presents
Replies: 11
Views: 5637

Re: Misplaced Christmas presents

Kinda brute forced it, since it's about number of kinds in families: (A,B,C)=(3,4,5) is what I got. I did it by realizing that at A they got C candies, at B they got A candies, and at C they got B candies. From that: C=cA-1 for some c, B=bC-1 for some b and A=B-1(otherwise more t...
by Demki
Sun Nov 24, 2013 10:08 am UTC
Forum: What If?
Topic: What-If 0072: "Loneliest Human"
Replies: 17
Views: 7772

Re: What-If 0072: "Loneliest Human"

bclark wrote:Can everyone in a large portion of the Earth just leave so I can break the record? I wonder how hard this would actually be.

It would be easier if you're near the south pole. You will have to stop boats from entering your disk of loneliness, but a few torpedos should do the trick.
by Demki
Tue Nov 05, 2013 2:37 pm UTC
Forum: What If?
Topic: What-If 0070: "The Constant Groundskeeper"
Replies: 26
Views: 7635

Re: What-If 0070: "The Constant Groundskeeper"

But that part about "just as you've finished, it's time to start over again" makes me think of the current insanity that is "software updates." I swear there's more time and bandwidth spent on updates to OS and apps than on actually using the dang things. :cry: . And then there'...
by Demki
Mon Oct 28, 2013 7:37 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1283: "Headlines"
Replies: 58
Views: 16864

Re: 1283: "Headlines"

Reminds me of this.
by Demki
Wed Oct 09, 2013 8:24 pm UTC
Forum: Mathematics
Topic: Product numeral system
Replies: 2
Views: 1187

Re: Product numeral system

25 = ||..| (or if you want | to be 0 and . to be 1: ..||.) 127 = ||||||| (or .......) 5623 = |.|.|||||.||| (or .|.|.....|...) Binary works, why ruin it? Also, with your system you can't represent 0. Binary requires only log 2 (n) bits for the number n. The only problem with binary is that you need t...

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