## maxima-bugs

 [Maxima-bugs] [ maxima-Bugs-3167269 ] sum fails with bound neq 0 From: SourceForge.net - 2011-01-28 20:00:18 ```Bugs item #3167269, was opened at 2011-01-28 21:00 Message generated for change (Tracker Item Submitted) made by fmaltey You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3167269&group_id=4933 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Lisp Core - Simplification Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: F.Maltey (fmaltey) Assigned to: Nobody/Anonymous (nobody) Summary: sum fails with bound neq 0 Initial Comment: I test this sum of k^2*binomial(n,k) The result is right for k in 0..n and k=1..n, isn't compute in 2..n, and is wrong from 3 to n. I get 0 with Sage in 2..n. (%i20) simplify_sum(sum(k^2*binomial(n,k),k,0,n)); 2 n (n + n) 2 (%o20) ----------- 4 (%i21) simplify_sum(sum(k^2*binomial(n,k),k,1,n)); 2 n (n + n) 2 (%o21) ----------- 4 (%i22) simplify_sum(sum(k^2*binomial(n,k),k,2,n)); n ==== \ 2 (%o22) > k binomial(n, k) / ==== k = 2 (%i23) simplify_sum(sum(k^2*binomial(n,k),k,3,n)); 2 n 2 (n + n) 2 - 8 n + 4 n (%o23) ------------------------ 4 ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3167269&group_id=4933 ```
 [Maxima-bugs] [ maxima-Bugs-3167269 ] sum fails with bound neq 0 From: SourceForge.net - 2011-04-24 09:03:59 ```Bugs item #3167269, was opened at 2011-01-28 21:00 Message generated for change (Settings changed) made by andrejv You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3167269&group_id=4933 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Lisp Core - Simplification Group: None Status: Open Resolution: None Priority: 5 Private: No Submitted By: F.Maltey (fmaltey) >Assigned to: Andrej Vodopivec (andrejv) Summary: sum fails with bound neq 0 Initial Comment: I test this sum of k^2*binomial(n,k) The result is right for k in 0..n and k=1..n, isn't compute in 2..n, and is wrong from 3 to n. I get 0 with Sage in 2..n. (%i20) simplify_sum(sum(k^2*binomial(n,k),k,0,n)); 2 n (n + n) 2 (%o20) ----------- 4 (%i21) simplify_sum(sum(k^2*binomial(n,k),k,1,n)); 2 n (n + n) 2 (%o21) ----------- 4 (%i22) simplify_sum(sum(k^2*binomial(n,k),k,2,n)); n ==== \ 2 (%o22) > k binomial(n, k) / ==== k = 2 (%i23) simplify_sum(sum(k^2*binomial(n,k),k,3,n)); 2 n 2 (n + n) 2 - 8 n + 4 n (%o23) ------------------------ 4 ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3167269&group_id=4933 ```
 [Maxima-bugs] [ maxima-Bugs-3167269 ] sum fails with bound neq 0 From: SourceForge.net - 2011-04-28 06:20:59 ```Bugs item #3167269, was opened at 2011-01-28 21:00 Message generated for change (Settings changed) made by andrejv You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3167269&group_id=4933 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Lisp Core - Simplification Group: None >Status: Closed >Resolution: Fixed Priority: 5 Private: No Submitted By: F.Maltey (fmaltey) Assigned to: Andrej Vodopivec (andrejv) Summary: sum fails with bound neq 0 Initial Comment: I test this sum of k^2*binomial(n,k) The result is right for k in 0..n and k=1..n, isn't compute in 2..n, and is wrong from 3 to n. I get 0 with Sage in 2..n. (%i20) simplify_sum(sum(k^2*binomial(n,k),k,0,n)); 2 n (n + n) 2 (%o20) ----------- 4 (%i21) simplify_sum(sum(k^2*binomial(n,k),k,1,n)); 2 n (n + n) 2 (%o21) ----------- 4 (%i22) simplify_sum(sum(k^2*binomial(n,k),k,2,n)); n ==== \ 2 (%o22) > k binomial(n, k) / ==== k = 2 (%i23) simplify_sum(sum(k^2*binomial(n,k),k,3,n)); 2 n 2 (n + n) 2 - 8 n + 4 n (%o23) ------------------------ 4 ---------------------------------------------------------------------- >Comment By: Andrej Vodopivec (andrejv) Date: 2011-04-28 08:20 Message: Fixed in git: (%i18) simplify_sum(sum(k^2*binomial(n,k),k,0,n)); (%o18) (n^2+n)*2^(n-2) (%i19) simplify_sum(sum(k^2*binomial(n,k),k,1,n)); (%o19) (n^2+n)*2^(n-2) (%i20) simplify_sum(sum(k^2*binomial(n,k),k,2,n)); (%o20) ((n^2+n)*2^n-4*n)/4 (%i21) simplify_sum(sum(k^2*binomial(n,k),k,3,n)); (%o21) ((n^2+n)*2^n-8*n^2+4*n)/4 ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3167269&group_id=4933 ```