There is a bug in sumcontract function: (%i5) sumcontract(sum(k, k, 1, n) + sum(k^2, k, 1, n)); Maxima encountered a Lisp error: Error in MACSYMA-TOP-LEVEL [or a callee]: The function $MAX is undefined. Automatically continuing. To reenable the Lisp debugger set *debugger-hook* to nil. A patch for this is attached. Andrej
Attached file: sumcon.lisp.patch