Flash Flash Revolution: Community Forums The Project Euler thread
 Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

 10-24-2011, 06:27 AM #61 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread i'm seriously advocating that the quickest method would be starting at the set for Co(100) and drawing each Co(n+1) from Co(n) __________________ ~*~Lurkadurk - 1134-7796-6967~*~
 10-24-2011, 10:26 AM #62 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread it's predictable though basically it comes down to an iterative process i think the hardest part would be how to arrange the arrays for optimal speed i was thinking that you would basically set it up like this: [a_2, a_3, a_5, a_7, ..., a_p] p is the largest prime below n, and the a_i are not necessarily distinct, so that when you actually wanted to find Co(n) you'd remove duplicates and add 1 __________________ ~*~Lurkadurk - 1134-7796-6967~*~ Last edited by FFR4EVA_00; 10-24-2011 at 10:47 AM..
 10-24-2011, 01:29 PM #63 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread __________________ ~*~Lurkadurk - 1134-7796-6967~*~ Last edited by FFR4EVA_00; 10-24-2011 at 03:46 PM..
 10-24-2011, 01:50 PM #64 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread like i said: the set doesn't have to be distinct in this arrangement i could easily just leave empty spaces but hey, programming doesn't really like those and 16 only has one factor i have no idea what you're talking about what's going on with 21 is this: if a < b < c, then ac+b > ab+c i just threw in the snippet about testing 20 because i figured a program would try it __________________ ~*~Lurkadurk - 1134-7796-6967~*~ Last edited by FFR4EVA_00; 10-24-2011 at 01:53 PM..
10-24-2011, 03:26 PM   #65
LongGone
-

Join Date: Jul 2008
Location: Malaysia
Age: 31
Posts: 1,679

__________________
My Solo Simfiles
My Solo Simfiles Part 2

Quote:
 Originally Posted by Choofers people age at a rate of about 1 year per year

10-24-2011, 03:58 PM   #66
FFR4EVA_00
FFR Player

Join Date: Aug 2005
Location: Banned
Posts: 1,770

longgone is correct on 1 and 2
here's what you're confused about if i am right:

Quote:
 [a_2, a_3, a_5, a_7, ..., a_p] p is the largest prime below n, and the a_i are not necessarily distinct, so that when you actually wanted to find Co(n) you'd remove duplicates and add 1
Quote:
 20 gets a bit more complex 20 drags in 16 and 15, but 15 is also a multiple of 3 it quickly becomes apparent that the only thing one could do with the 3 is use 9 20+9 < 16+15, don't insert 20 : [16, 15, 15, 7, 11, 13, 17, 19] 21+5 > 15+7, insert [16, 21, 5, 21, 11, 13, 17, 19] 20 < 16+5, don't attempt
__________________

10-24-2011, 04:18 PM   #67
Knut.Angstrom
FFR Player

Join Date: Oct 2011
Posts: 3

Quote:
 Originally Posted by Reincarnate A step-by-step runthrough of the Co(100) process:
Your sum 1355 is not correct since you use 99 instead of 88 giving 1356

 10-24-2011, 04:24 PM #68 Knut.Angstrom FFR Player   Join Date: Oct 2011 Posts: 3 Re: THE project euler thread 1+64+81+25+49+11+13+17+19+23+29+31+37+41+43+47+53+59+61+67+71+73+79+83+89+97+ (95-25-19)+(91-49-13)+(88-64-11) =1356
 10-24-2011, 04:25 PM #69 fido123 FFR Player     Join Date: Sep 2005 Age: 30 Posts: 4,189 Re: THE project euler thread Worked on this for a little bit one night. Did 1, 2, and 6 all in C: Question 1: Question 2: Question 6: Easy stuff so far but I'm not really all that knowledgeable about math at all so I'm not sure how far I'll get with this lol. Last edited by fido123; 10-24-2011 at 04:28 PM..
10-24-2011, 04:28 PM   #70
FFR4EVA_00
FFR Player

Join Date: Aug 2005
Location: Banned
Posts: 1,770

Quote:
 Originally Posted by Reincarnate Okay but what about needing to retrieve something lost? For instance, the solution to Co(100) includes a 17, which gets removed back in Co(51)

Quote:
 Originally Posted by Reincarnate Also some numbers will have more than 1 unique prime factor
i heard whispers that this is true but i am trying to rigorously disprove it
__________________

Last edited by FFR4EVA_00; 10-24-2011 at 04:33 PM..

 10-24-2011, 04:56 PM #71 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread yeah, i never said what those were, i'm sorry a_p is just the number that is divisible by p in whatever set we're looking at (since we're supposed to be looking at coprime sets there is exactly one a_p for every p but not all a_p are unique) the reason why i'm duplicating the terms is that i think it will be easier for a computer to traverse __________________ ~*~Lurkadurk - 1134-7796-6967~*~ Last edited by FFR4EVA_00; 10-24-2011 at 04:58 PM..
10-24-2011, 05:18 PM   #72
LongGone
-

Join Date: Jul 2008
Location: Malaysia
Age: 31
Posts: 1,679

Quote:
 Originally Posted by Reincarnate Also some numbers will have more than 1 unique prime factors (e.g. 30 -> unique primes 2, 3, and 5)
__________________
My Solo Simfiles
My Solo Simfiles Part 2

Quote:
 Originally Posted by Choofers people age at a rate of about 1 year per year

Last edited by LongGone; 10-24-2011 at 05:22 PM..

10-24-2011, 05:22 PM   #73
Reincarnate
x'); DROP TABLE FFR;--

Join Date: Nov 2010
Posts: 6,334

Quote:
 Originally Posted by LongGone
I think this is a reasonable assumption to make

Last edited by Reincarnate; 10-26-2011 at 01:41 PM..

 10-24-2011, 06:04 PM #74 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread @Reincarnate- that is correct, yes now i'm messing around with a brute-force solution of sorts though, NOTHING like what i was doing before __________________ ~*~Lurkadurk - 1134-7796-6967~*~
 10-24-2011, 07:42 PM #75 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread __________________ ~*~Lurkadurk - 1134-7796-6967~*~
 10-24-2011, 08:19 PM #76 Reincarnate x'); DROP TABLE FFR;--     Join Date: Nov 2010 Posts: 6,334 Re: THE project euler thread congrats FFR4, nicely done
 10-25-2011, 12:44 AM #77 stargroup100 behanjc & me are <3'ers   Join Date: Jul 2006 Posts: 2,046 Re: THE project euler thread http://img268.imageshack.us/img268/5532/eulero.jpg I got 0 eulerian points for this. mad __________________ Rhythm Simulation Guide Comments, criticism, suggestions, contributions, etc. are all welcome. Piano Etude Demon Fire sheet music
 10-25-2011, 08:53 AM #78 iironiic D6 FFR Legacy Player     Join Date: Jan 2009 Age: 30 Posts: 4,211 Re: THE project euler thread Got #71 with pencil and paper xD EDIT: Nice FFREva!
 10-25-2011, 09:41 AM #79 FFR4EVA_00 FFR Player     Join Date: Aug 2005 Location: Banned Posts: 1,770 Re: THE project euler thread http://projecteuler.net/eulerians "For the twelve most recent problems the difference, d, in the length of time to solve the problem (in minutes) between each member and the slowest in the table is calculated and log2(max(d,2)) points are awarded." so every time someone solves the problem, the points of everyone who already solved it go up in other words cosmovibe has 8 points now __________________ ~*~Lurkadurk - 1134-7796-6967~*~
 10-25-2011, 10:58 AM #80 Reincarnate x'); DROP TABLE FFR;--     Join Date: Nov 2010 Posts: 6,334 Re: THE project euler thread Last edited by Reincarnate; 10-25-2011 at 11:01 AM..

 Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are Off [IMG] code is On HTML code is Off Forum Rules
 Forum Jump User Control Panel Private Messages Subscriptions Who's Online Search Forums Forums Home Flash Flash Revolution     FFR General Talk         Songs of the Week         Bug Reports and Suggestions         Contested Chart Difficulties     FFR Events         Tournaments         FFR Trading Card Game     FFR Batch Forum         Active Sets         Completed Sets         FFR Songs and Artist Permissions     Brag Board         Brag Board Archives     FFR Profiles General Discussion     Chit Chat         Birthdays         Ask Me Anything     Introductions     Critical Thinking         Homework & Help     Technology Gaming     Stepmania         Simulator Files     Other Music Games     The Werewolf Game         TWG Archives     Other Forum Games     Video Games Life and Arts     Art and Graphics     Audio and Music Production     Films and Television     Writing and Literature     Health and Fitness     Sports

All times are GMT -5. The time now is 05:46 AM.