LIB "tst.lib"; tst_init(); option(redSB); ring R=0,(x,y),lp; ideal a1=x; ideal a2=y2+2y+1,x-1; ideal a3=y2-2y+1,x-1; ideal I=intersect(a1,a2,a3); poly h=y4-2y2+1; ideal I1=quotient(I,h); ideal rad=I1; ideal I2=std(I,h); dim(I2); ideal u=finduni(I2); u; I2=I2,x2-1,y2-1; rad=intersect(rad,I2); rad; tst_status(1);$