Message Boards

14463 Views

7 Replies

1 Total Likes

View groups...

Follow this post

Share this post:

GROUPS:

Mathematics Mathematica Wolfram|Alpha Calculus Wolfram Language

Bug in LaguerreL Limit ?

Posted 10 years ago

I have found a bug in Limit. I have Mathematica 10.0.1.0 on Windows 8.1. Limit[(n!* LaguerreL[ n, -1]/(n^(n + 1/4)/Sqrt[2]/E^(n - 2 Sqrt[n] + 1/2)) - 1) Sqrt[n], n -> 1000] // N Output: 0.649562 Limit[(n!* LaguerreL[ n, -1]/(n^(n + 1/4)/Sqrt[2]/E^(n - 2 Sqrt[n] + 1/2)) - 1) Sqrt[n], n -> Infinity] Output:13/16 = 0.8125

I have found a bug in Limit. I have Mathematica 10.0.1.0 on Windows 8.1.

enter image description here

Limit[(n!*
      LaguerreL[
        n, -1]/(n^(n + 1/4)/Sqrt[2]/E^(n - 2 Sqrt[n] + 1/2)) - 
     1) Sqrt[n], n -> 1000] // N

Output: 0.649562

Limit[(n!*
      LaguerreL[
        n, -1]/(n^(n + 1/4)/Sqrt[2]/E^(n - 2 Sqrt[n] + 1/2)) - 
     1) Sqrt[n], n -> Infinity]

Output:13/16 = 0.8125

POSTED BY: Mariusz Iwaniuk

7 Replies

Sort By:

Posted 10 years ago

Yes, all clear now. In future please remember to cite appropriately (that's a general rule) and to mention when an issue is posted elsewhere (that can save readers time). The bug, by the way, involves a subtle issue in `Series` code.

POSTED BY: Daniel Lichtblau

Posted 10 years ago

I wanted to help him and other users. Vaclav Kotesovec wrote: I already reported this bug in 2012, but still was not fixed (in versions 7,8,9,10) http://code.google.com/p/mathematica/issues/list see Issue 46. Dr. Wolfgang Hintze wrote: I see the question: why didn't Wolfram solve the bug? Also it might be interesting information fo other users (like myself). and now all clear.

POSTED BY: Mariusz Iwaniuk

Posted 10 years ago

When you say "I have found a bug in Limit" do you mean you found it on another forum? If so, that should be mentioned explicitly, so as to avoid any appearance of claiming credit for another's work.