i1 : C = resolution cokernel matrix {{4,5}} 1 1 o1 = ZZ <-- ZZ 0 1 o1 : ChainComplex
i2 : C ++ C[-2] 1 1 1 1 o2 = ZZ <-- ZZ <-- ZZ <-- ZZ 0 1 2 3 o2 : ChainComplex
The source of this document is in OldChainComplexes/docs/doc9.m2:316:0.