new prime part derived functor

lib/FreeGmodules/wordOperations.gi

@@ -256,6 +256,8 @@ end);
 InstallGlobalFunction(MultiplyWord,
 function(n,w)
 local v, u, i,x;
+if n=1 then return w; fi;
+
 v:=[];
 
 u:=1*w; 

lib/Functors/equiChainMap.gi

@@ -117,13 +117,18 @@ local z,u,a,y;
 if not IsBound(mapgensRec[m+1][AbsoluteValue(x[1])][x[2]]) then
 
 if not x[2]=IDEL then
+############################
 y:=ShallowCopy(mapgens([x[1],IDEL],m));
+
 Apply(y,b->[b[1],Mult(GhomQ(x[2]),b[2])]);
 
+if x[2]<10000 then     
 	if x[1]>0 then mapgensRec[m+1][AbsoluteValue(x[1])][x[2]]:=y;
 	else
 	mapgensRec[m+1][AbsoluteValue(x[1])][x[2]]:=NegateWord(y);
 	fi;
+fi;
+#############################
 return y;
 fi;
    if m=0 then 
@@ -141,11 +146,13 @@ fi;
    u:=[];
 ##########################
 if Charact=0 then 
+
  for a in Collected(z) do
       Append(u,MultiplyWord(a[2],
 List(HomotopyS(m-1,a[1]), t->[t[1],Mult(GhomQ(x[2]),t[2])])
 ));
       od;
+
 else
       for a in Collected(z) do
       Append(u,MultiplyWord(a[2] mod Charact,
@@ -176,7 +183,9 @@ local a, u,v,x,y,z;
 
 v:=Collected(w);
 if Charact=0 then
+
 Apply(v,x->MultiplyWord(x[2],  mapgens(x[1],m)));
+
 else
 Apply(v,x->MultiplyWord(x[2] mod Charact,  mapgens(x[1],m)));
 fi;

lib/Functors/primePartDerivedvsgc.gi

@@ -44,22 +44,38 @@ HPrels:=[Identity(HP)];
 
 #########################################
 #########################################
-AddRels:=function(Q,L)  #Here P < Q < G where P=Syl_p(G)
-local i, hh, Lhh, gg, g, gg1, h, sylQQ, QQ, xx, RC, gens, bool;
-
+AddRels:=function(chn,L)  #chn=[P = Q1 < <Q2 < ... < Qk=Q] is a chain of 
+                          #k subgroups in G with P=Syl_p(G)
+local Q, NS, i, hh, Lhh, ggg, gg, g, gg1, h, sylQQ, QQ, xx, RC, gens, bool, Q0, Q1, S, SS;
+Q:=chn[Length(chn)];
 QQ:=Intersection(Q,Q^L); 
 sylQQ:=SylowSubgroup(QQ,prime);
 if not Order(sylQQ)>1 then return; fi;
-gens:=SmallGeneratingSet(sylQQ);
-
-RC:=RightTransversal(Q,Normalizer(Q,sylQQ));
-for g in RC do                #December 2024 changed 
+gg:=One(G);
+
+for i in [1..Length(chn)-1] do
+################
+################  Changed January 2025
+S:=sylQQ^gg;
+gens:=SmallGeneratingSet(S);
+Q0:=chn[Length(chn)-i+1];
+Q1:=chn[Length(chn)-i];
+NS:=Normalizer(Q0,Q1);
+RC:=RightTransversal(Q0,NS); 
+RC:=List(RC,x->x^-1);
+
+Unbind(ggg);
+for g in RC do             
 bool:=true;
    for xx in gens do
-      if not xx^g in P then bool:=false; break; fi;
+      if not xx^g in Q1 then bool:=false; break; fi;
    od;
-if bool then gg:=g; break; fi; 
-#if IsSubgroup(P,sylQQ^g) then gg:=g; break; fi;
+if bool then ggg:=g; break; fi; 
+od;
+################
+################
+gg:=gg*ggg;
+
 od;
 
 
@@ -98,18 +114,47 @@ Image(HPKhomHP, Image(HKhomHPK,x) ) );
 
 fx:=GroupHomomorphismByFunction(sylQQ,Q,g->g^(L^-1));
 imfx:=Image(fx);
-#hh:=false;
-#RC:=ConjugateSubgroups(Q,imfx);
-#i:=PositionProperty(RC,x->IsSubgroup(P,x));
-#hh:=RepresentativeAction(Q,imfx,RC[i]);
-
-RC:=RightCosets(Q,Normalizer(Q,imfx));
-RC:=List(RC,Representative);
-for h in RC do                   #December 2024 changed from Q to RC
-if IsSubgroup(P,imfx^h) then hh:=h; break; fi;
+
+hh:=One(G);
+
+for i in [1..Length(chn)-1] do
+################
+################  Changed January 2025
+SS:=imfx^hh;
+gens:=SmallGeneratingSet(SS);
+Q0:=chn[Length(chn)-i+1];
+Q1:=chn[Length(chn)-i];
+NS:=Normalizer(Q0,Q1);
+RC:=RightTransversal(Q0,NS);
+RC:=List(RC,x->x^-1);
+
+Unbind(ggg);
+for h in RC do
+bool:=true;
+   for xx in gens do
+      if not xx^h in Q1 then bool:=false; break; fi;
+   od;
+if bool then ggg:=h; break; fi;
+od;
+################
+################
+hh:=hh*ggg;
+
 od;
+
+
+#######################
+#######################
+#RC:=RightCosets(Q,Normalizer(Q,imfx));
+#RC:=List(RC,Representative);
+#for h in RC do                   #December 2024 changed from Q to RC
+#if IsSubgroup(P,imfx^h) then hh:=h; break; fi;
+#od;
+#######################
+#######################
+
+
 Lhh:=L^-1*hh;
-#fx:=GroupHomomorphismByFunction(sylQQ,P,g->(g^(L^-1))^hh);
 fx:=GroupHomomorphismByFunction(sylQQ,P,g->g^Lhh);
 
 xx:=F(EquivariantChainMap(S,R,fx));
@@ -139,7 +184,7 @@ ord:=function(x,y); return Order(x)<Order(y); end;
 if Order(P1)>Order(P) then 
 DCRS:=SmallGeneratingSet(P1);
    for L in DCRS do
-   AddRels(P,L);
+   AddRels([P],L);
    od;
 fi;
 for i in [2..Length(AscChn)] do
@@ -156,7 +201,7 @@ DCRS:=Filtered(DCRS,a->not a in Cent);  #This does not achieve much
 
    for L in DCRS do
    cnt:=cnt+1;
-   AddRels(AscChn[i-1],L);
+   AddRels(AscChn{[1..i-1]},L);
    od;
 od;
 #########################################

lib/Perturbations/resNormalSer.gi

@@ -49,9 +49,12 @@ od;
 
 GensQ[L]:=GensSeries[1];
 
-
 Res:=[];
+if tietze=false and Charact=0 then
+Res[2]:=ResolutionGenericGroup(Group(GensQ[2]),n);
+else
 Res[2]:=ResolutionFiniteGroup(GensQ[2],n,tietze,Charact);
+fi;
 #Res[2]:=ResolutionFiniteGroup(Group(GensQ[2]),n,tietze,Charact); 
 #Changed 14/08/2019
 if nohomotopy then Res[2]!.homotopy:=fail; fi;

tst/testall2/3.5.3.tst

@@ -4,5 +4,6 @@ gap> SetCrystGroupDefaultAction( RightAction );
 gap> e:=SpaceGroupBBNWZ(2,10);;
 gap> G:=RelativeCentralQuotientSpaceGroup(e,4);;
 gap> n:=10;;PoincareSeries(G,n);
+The series is guaranteed correct for group cohomology in degrees < 11
 (1)/(-x_1^4+2*x_1^3-2*x_1+1)
 gap> STOP_TEST( "tst.tst", 1000 );