Hi all, In sage, as of 4.1.1, binomial( -7, 1 ) returns -7. As I understand the definition of binomial, this should be 0, since there is no set with -7 elements.
Axiom returns 0 in this case. This is not really a "problem" but does give *interesting* results, when summing binomials over all integers. For some value of all. That is, sum( [ binomial( 3 + i, 2 ) * binomial( 15 - i, 3 ) for i in [-1..12] ] ) should be the same as sum( [ binomial( 3 + i, 2 ) * binomial( 15 - i, 3 ) for i in [-14..100] ] ) Johann --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
