i1 : S = ZZ/10007[x,y];
i2 : betti coker matrix{{x^3,x*y^2},{y*x^2,y^3}} 0 1 o2 = total: 2 2 -1: . 2 0: 2 . o2 : BettiTally
i3 : betti coker map(S^{0,-1},,matrix{{x^2,y},{y^3,x^2}}) 0 1 o3 = total: 2 2 -1: . 2 0: 2 . o3 : BettiTally