All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Just Math
2 equal sums (Posted on 2016-04-11) Difficulty: 3 of 5
What is the largest n for which
1^2+2^2+3^2+ ... +n^2 = 1+2+3+ ... +m has a solution
with integer values of n & m?.

No Solution Yet Submitted by Ady TZIDON    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
re: computer exploration -- possible spoiler | Comment 2 of 3 |
(In reply to computer exploration -- possible spoiler by Charlie)

UBASIC, with extended precision has verified 85 as the highest n under 10 million that satisfies the criterion.


  10    sqs = 0      
  20    For n = 1 To 9999999
  30      sqs = sqs + n * n
  40      mp = Sqr(sqs * 2)
  50      m = Int(mp)
  60      If m * (m + 1) / 2 = sqs Then
  70         :print n , Str(m) , "    " , Str(sqs) 
  80    Next

  Posted by Charlie on 2016-04-11 22:44:38
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (3)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information