Problem 647

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DeKlod
Posts: 19
Joined: Tue Aug 21, 2018 8:55 am

Problem 647

Post by DeKlod »

Hello all,
I know that quite some folk have solved this one already and it doesn't look too daunting, really - except that: well I'm getting 186 and not 184 as result for F_3(100).
Is that a typo that has been missed because people have gone straight on to the grown-up stuff with Sigma_k F_k(10^3) - or should I perhaps go and study Chapter 2 of 'Basic Arithmetic for Massive Dummies'?
Any input is welcome. Cheers,
Claude
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jaap
Posts: 553
Joined: Tue Mar 25, 2008 3:57 pm
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Re: Problem 647

Post by jaap »

DeKlod wrote: Fri May 17, 2019 4:38 pm I know that quite some folk have solved this one already and it doesn't look too daunting, really - except that: well I'm getting 186 and not 184 as result for F_3(100).
It really is 184. If you want, you can send me the pairs (A,B) that make up the sum by private message (you should have only four, and remember that A, B are positive so non-zero), and I'll tell you what is wrong.
DeKlod
Posts: 19
Joined: Tue Aug 21, 2018 8:55 am

Re: Problem 647

Post by DeKlod »

Thanks for your quick response, jaap.
And thanks also for the offer of a PM conversation. I won't bother you just yet as I've actually only got three pairs so clearly there's something massively wrong with my approach.
Back to the drawing board then.
Cheers,
Claude

********
EDIT 10 minutes later: Now I get 184 with 4 couples... Forgot the simplest of basic checks. Would it be Friday today by any chance?
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