There is a strange bug in cvs, which appears when maxima is compiled
with cmucl and sbcl, but does not appear when maxima is compiled with
gcl.
With gcl it is ok:
(%i1) build_info()$
Maxima version: 5.11.0cvs
Maxima build date: 18:50 3/19/2007
host type: i686-pc-linux-gnu
lisp-implementation-type: GNU Common Lisp (GCL)
lisp-implementation-version: GCL 2.6.8
(%i2) s : 2*sum(k, k, 1, n);
(%o2) 2*sum(k,k,1,n)
(%i3) intosum(s);
(%o3) sum(2*k,k,1,n)
(%i4) intosum(s);
(%o4) sum(2*k,k,1,n)
With cmucl it is wrong:
(%i1) build_info()$
Maxima version: 5.11.0cvs
Maxima build date: 18:53 3/19/2007
host type: i686-pc-linux-gnu
lisp-implementation-type: CMU Common Lisp
lisp-implementation-version: CVS release-19a 19a-release-20040728 +
minimal debian patches
(%i2) s : 2*sum(k, k, 1, n);
(%o2) 2*sum(k,k,1,n)
(%i3) intosum(s);
(%o3) 2*sum(k,k,1,n)
(%i4) intosum(s);
(%o4) 4*sum(k,k,1,n)
(%i5) intosum(s);
(%o5) 8*sum(k,k,1,n)
(%i6) intosum(s);
(%o6) 16*sum(k,k,1,n)
This bug was not present in 5.11. It would be good to fix it before
the next release, but I have no idea what could be wrong.
--
Andrej