-- -*- M2-comint -*- {* hash: 655370177 *} i1 : R = QQ[x,y,z]/ideal(x*y^2-z^9) o1 = R o1 : QuotientRing i2 : J = ideal(x,y,z) o2 = ideal (x, y, z) o2 : Ideal of R i3 : I = reesIdeal(J, Variable => p) 8 2 o3 = ideal (z*p - y*p , z*p - x*p , y*p - x*p , x*y*p - z p , x*p - 1 2 0 2 0 1 1 2 1 ------------------------------------------------------------------------ 7 2 2 6 3 z p , p p - z p ) 2 0 1 2 o3 : Ideal of R[p , p , p ] 0 1 2 i4 : describe ring I o4 = R[p , p , p , Degrees => {3:{1}}, Heft => {1, 0}, MonomialOrder => 0 1 2 {1} ------------------------------------------------------------------------ {MonomialSize => 32}, DegreeRank => 2] {GRevLex => {3:1} } {Position => Up } i5 : I1 = first flattenRing I 9 2 8 2 o5 = ideal (- z + x*y , p z - p y, p z - p x, p y - p x, p x*y - p z , p x - 1 2 0 2 0 1 1 2 1 ------------------------------------------------------------------------ 2 7 2 3 6 p z , p p - p z ) 2 0 1 2 o5 : Ideal of QQ[p , p , p , x, y, z] 0 1 2 i6 : describe ring oo o6 = QQ[p , p , p , x..z, Degrees => {3:{1}, 3:{0}}, Heft => {0..1}, MonomialOrder => {MonomialSize => 32}, DegreeRank => 2] 0 1 2 {1} {1} {GRevLex => {3:1} } {Position => Up } {GRevLex => {3:1} } i7 : S = newRing(ring I1, Degrees=>{numgens ring I1:1}) o7 = S o7 : PolynomialRing i8 : describe S o8 = QQ[p , p , p , x..z, Degrees => {6:1}, Heft => {1}, MonomialOrder => {MonomialSize => 32}, DegreeRank => 1] 0 1 2 {GRevLex => {3:1} } {Position => Up } {GRevLex => {3:1} } i9 : I2 = sub(I1,vars S) 9 2 8 2 o9 = ideal (- z + x*y , p z - p y, p z - p x, p y - p x, p x*y - p z , p x - 1 2 0 2 0 1 1 2 1 ------------------------------------------------------------------------ 2 7 2 3 6 p z , p p - p z ) 2 0 1 2 o9 : Ideal of S i10 : res I2 1 7 11 6 1 o10 = S <-- S <-- S <-- S <-- S <-- 0 0 1 2 3 4 5 o10 : ChainComplex i11 :