Opened 12 years ago

Closed 12 years ago

# Maxima returns wrong value for sum(binomial(j,k),j,k,n)

Reported by: Owned by: jpflori burcin major sage-duplicate/invalid/wontfix symbolics maxima Fixed upstream, in a later stable release.

### Description

The -1 should not be here:

sage: sum(binomial(j,k),j,k,k+1)
k + 2
sage: sum(binomial(j,k),j,k,n)
binomial(n + 1, k + 1) - 1
sage: sum(binomial(j,k),j,k,n).subs({n:k+1})
binomial(k + 2, k + 1) - 1
sage: maxima_console()
Maxima 5.20.1 http://maxima.sourceforge.net
using Lisp ECL 10.2.1
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.
(%o1) /home/jp/boulot/sage/sage-4.6/local/share/maxima/5.20.1/share/contrib/so\
lve_rec/simplify_sum.mac
(%i2) sum(binomial(j,k),j,k,n);
n
====
\
(%o2)                         >    binomial(j, k)
/
====
j = k
(%i3) simplify_sum(%);
(%o3)                     binomial(n + 1, k + 1) - 1
(%i4) sum(binomial(j,k),j,0,n);
n
====
\
(%o4)                         >    binomial(j, k)
/
====
j = 0
(%i5) simplify_sum(%);
(%o5)             binomial(n + 1, k + 1) - binomial(1, k + 1)

### comment:1 Changed 12 years ago by jpflori

Report Upstream: N/A → Fixed upstream, in a later stable release.

I just tested it with Maxima 5.22.1 and Ecl from #10187 and the result is now correct. So updating to that version will fix this problem.

sage: maxima_console()
Maxima 5.22.1 http://maxima.sourceforge.net
using Lisp ECL 10.4.1
Dedicated to the memory of William Schelter.
The function bug_report() provides bug reporting information.

(%o1) /home/jp/boulot/sage/sage-4.6/local/share/maxima/5.22.1/share/contrib/so\
lve_rec/simplify_sum.mac
(%i2) sum(binomial(j,k),j,k,n);

n
====
\
(%o2)                         >    binomial(j, k)
/
====
j = k
(%i3) simplify_sum(%);

(%o3)                       binomial(n + 1, k + 1)
(%i4) sum(binomial(j,k),j,0,n);

n
====
\
(%o4)                         >    binomial(j, k)
/
====
j = 0
(%i5) simplify_sum(%);

(%o5)             binomial(n + 1, k + 1) - binomial(0, k + 1)
sage: x,y,z=var('x,y,z')
sage: i,j,k,n,m,d=var('i,j,k,n,m,d')
sage: sum(binomial(j,k),j,k,n)
binomial(n + 1, k + 1)

### comment:2 Changed 12 years ago by jpflori

Keywords: maxima added → duplicate new → closed

Sorry for the noise, it was already mentionned here: #7952

However the patch to maxima was not included yet.

### comment:3 Changed 12 years ago by mvngu

Milestone: → sage-duplicate/invalid/wontfix
Note: See TracTickets for help on using tickets.