Problem 403

[mctrafik]

This is a stupid question,
but what lattice points are being referred to? Dimond, rectangle or square? So like are the coordinates like (0, 0), (0, 1) .. (1, 0), (1, 1) .... or something else?
A picture would be nice

[hk]

Here's an illustration of L(1,2)=8:

403.gif

So nothing esoterical and drawable manually on graph paper.

[mctrafik]

I'm sorry. What? 403.gif? Where is it?

[sivakd]

Here is one I created.

[mctrafik]

Thank you! Most helpful!

[hk]

I'm sorry. What? 403.gif? Where is it?

Mysteriously it was gone. Uploaded again.

[mctrafik]

Maybe someone else got the same problem. I keep getting S(5) = 360. Can't seem to find where I'm going wrong.

Here are the (a, b) pairs I'm getting and how many points are there between the line and the parabola:

Code: Select all

  0   0 [1]
  0   1 [4]
  1   0 [2]
 -1   0 [2]
  1   2 [8]
 -1   2 [8]
  2  -1 [1]
 -2  -1 [1]
  2   0 [4]
 -2   0 [4]
  3  -2 [2]
 -3  -2 [2]
  3   0 [9]
 -3   0 [9]
  0   4 [15]
  2   3 [15]
 -2   3 [15]
  3   4 [27]
 -3   4 [27]
  4  -4 [1]
 -4  -4 [1]
  4  -3 [4]
 -4  -3 [4]
  5  -4 [9]
 -5  -4 [9]
  4   0 [16]
 -4   0 [16]
  4   5 [43]
 -4   5 [43]
  5   0 [29]
 -5   0 [29]

[luckyrodman]

It's you again!!!

Why do you always ask:"Please tell me where I'm going wrong?" You can see there are already 63 solvers but no one come here to ask for more hints to solve it.

Please remember that problems on ProjectEuler are neither job nor homework. This problem is a difficult one. It is too hard for beginners. I suggest you can do older but simpler problems to get some knowledge before you try the newest problems.

And please remember that this board is used for clarifications when you don't understand the problem statement.

[hk]

@ mctrafik: your lattice points count is off for several a,b pairs. Not telling more.
Good luck.

[mctrafik]

@ mctrafik: your lattice points count is off for several a,b pairs.

Excellent. That's what I was hoping to hear. Just wanted to make sure I got (a, b) pairs correctly. Thank you.

[hk]

@ LuckyRodman and mctrafik: please keep both to the topic: Project Euler Clarifications.
In my opinion you're both off topic.