edit this statistic or download as text // json
Identifier
Values
=>
Cc0005;cc-rep
[1,0]=>0 [1,0,1,0]=>1 [1,1,0,0]=>0 [1,0,1,0,1,0]=>2 [1,0,1,1,0,0]=>1 [1,1,0,0,1,0]=>1 [1,1,0,1,0,0]=>1 [1,1,1,0,0,0]=>0 [1,0,1,0,1,0,1,0]=>3 [1,0,1,0,1,1,0,0]=>2 [1,0,1,1,0,0,1,0]=>1 [1,0,1,1,0,1,0,0]=>2 [1,0,1,1,1,0,0,0]=>1 [1,1,0,0,1,0,1,0]=>2 [1,1,0,0,1,1,0,0]=>1 [1,1,0,1,0,0,1,0]=>2 [1,1,0,1,0,1,0,0]=>2 [1,1,0,1,1,0,0,0]=>1 [1,1,1,0,0,0,1,0]=>1 [1,1,1,0,0,1,0,0]=>1 [1,1,1,0,1,0,0,0]=>1 [1,1,1,1,0,0,0,0]=>0 [1,0,1,0,1,0,1,0,1,0]=>4 [1,0,1,0,1,0,1,1,0,0]=>3 [1,0,1,0,1,1,0,0,1,0]=>2 [1,0,1,0,1,1,0,1,0,0]=>3 [1,0,1,0,1,1,1,0,0,0]=>2 [1,0,1,1,0,0,1,0,1,0]=>2 [1,0,1,1,0,0,1,1,0,0]=>1 [1,0,1,1,0,1,0,0,1,0]=>2 [1,0,1,1,0,1,0,1,0,0]=>3 [1,0,1,1,0,1,1,0,0,0]=>2 [1,0,1,1,1,0,0,0,1,0]=>1 [1,0,1,1,1,0,0,1,0,0]=>1 [1,0,1,1,1,0,1,0,0,0]=>2 [1,0,1,1,1,1,0,0,0,0]=>1 [1,1,0,0,1,0,1,0,1,0]=>3 [1,1,0,0,1,0,1,1,0,0]=>2 [1,1,0,0,1,1,0,0,1,0]=>1 [1,1,0,0,1,1,0,1,0,0]=>2 [1,1,0,0,1,1,1,0,0,0]=>1 [1,1,0,1,0,0,1,0,1,0]=>3 [1,1,0,1,0,0,1,1,0,0]=>2 [1,1,0,1,0,1,0,0,1,0]=>3 [1,1,0,1,0,1,0,1,0,0]=>2 [1,1,0,1,0,1,1,0,0,0]=>2 [1,1,0,1,1,0,0,0,1,0]=>1 [1,1,0,1,1,0,0,1,0,0]=>2 [1,1,0,1,1,0,1,0,0,0]=>2 [1,1,0,1,1,1,0,0,0,0]=>1 [1,1,1,0,0,0,1,0,1,0]=>2 [1,1,1,0,0,0,1,1,0,0]=>1 [1,1,1,0,0,1,0,0,1,0]=>2 [1,1,1,0,0,1,0,1,0,0]=>2 [1,1,1,0,0,1,1,0,0,0]=>1 [1,1,1,0,1,0,0,0,1,0]=>2 [1,1,1,0,1,0,0,1,0,0]=>2 [1,1,1,0,1,0,1,0,0,0]=>2 [1,1,1,0,1,1,0,0,0,0]=>1 [1,1,1,1,0,0,0,0,1,0]=>1 [1,1,1,1,0,0,0,1,0,0]=>1 [1,1,1,1,0,0,1,0,0,0]=>1 [1,1,1,1,0,1,0,0,0,0]=>1 [1,1,1,1,1,0,0,0,0,0]=>0 [1,0,1,0,1,0,1,0,1,0,1,0]=>5 [1,0,1,0,1,0,1,0,1,1,0,0]=>4 [1,0,1,0,1,0,1,1,0,0,1,0]=>3 [1,0,1,0,1,0,1,1,0,1,0,0]=>4 [1,0,1,0,1,0,1,1,1,0,0,0]=>3 [1,0,1,0,1,1,0,0,1,0,1,0]=>2 [1,0,1,0,1,1,0,0,1,1,0,0]=>2 [1,0,1,0,1,1,0,1,0,0,1,0]=>3 [1,0,1,0,1,1,0,1,0,1,0,0]=>4 [1,0,1,0,1,1,0,1,1,0,0,0]=>3 [1,0,1,0,1,1,1,0,0,0,1,0]=>2 [1,0,1,0,1,1,1,0,0,1,0,0]=>2 [1,0,1,0,1,1,1,0,1,0,0,0]=>3 [1,0,1,0,1,1,1,1,0,0,0,0]=>2 [1,0,1,1,0,0,1,0,1,0,1,0]=>3 [1,0,1,1,0,0,1,0,1,1,0,0]=>2 [1,0,1,1,0,0,1,1,0,0,1,0]=>1 [1,0,1,1,0,0,1,1,0,1,0,0]=>2 [1,0,1,1,0,0,1,1,1,0,0,0]=>1 [1,0,1,1,0,1,0,0,1,0,1,0]=>3 [1,0,1,1,0,1,0,0,1,1,0,0]=>2 [1,0,1,1,0,1,0,1,0,0,1,0]=>4 [1,0,1,1,0,1,0,1,0,1,0,0]=>3 [1,0,1,1,0,1,0,1,1,0,0,0]=>3 [1,0,1,1,0,1,1,0,0,0,1,0]=>2 [1,0,1,1,0,1,1,0,0,1,0,0]=>2 [1,0,1,1,0,1,1,0,1,0,0,0]=>3 [1,0,1,1,0,1,1,1,0,0,0,0]=>2 [1,0,1,1,1,0,0,0,1,0,1,0]=>2 [1,0,1,1,1,0,0,0,1,1,0,0]=>1 [1,0,1,1,1,0,0,1,0,0,1,0]=>2 [1,0,1,1,1,0,0,1,0,1,0,0]=>2 [1,0,1,1,1,0,0,1,1,0,0,0]=>1 [1,0,1,1,1,0,1,0,0,0,1,0]=>2 [1,0,1,1,1,0,1,0,0,1,0,0]=>2 [1,0,1,1,1,0,1,0,1,0,0,0]=>3 [1,0,1,1,1,0,1,1,0,0,0,0]=>2 [1,0,1,1,1,1,0,0,0,0,1,0]=>1 [1,0,1,1,1,1,0,0,0,1,0,0]=>1 [1,0,1,1,1,1,0,0,1,0,0,0]=>1 [1,0,1,1,1,1,0,1,0,0,0,0]=>2 [1,0,1,1,1,1,1,0,0,0,0,0]=>1 [1,1,0,0,1,0,1,0,1,0,1,0]=>4 [1,1,0,0,1,0,1,0,1,1,0,0]=>3 [1,1,0,0,1,0,1,1,0,0,1,0]=>2 [1,1,0,0,1,0,1,1,0,1,0,0]=>3 [1,1,0,0,1,0,1,1,1,0,0,0]=>2 [1,1,0,0,1,1,0,0,1,0,1,0]=>2 [1,1,0,0,1,1,0,0,1,1,0,0]=>1 [1,1,0,0,1,1,0,1,0,0,1,0]=>2 [1,1,0,0,1,1,0,1,0,1,0,0]=>3 [1,1,0,0,1,1,0,1,1,0,0,0]=>2 [1,1,0,0,1,1,1,0,0,0,1,0]=>1 [1,1,0,0,1,1,1,0,0,1,0,0]=>1 [1,1,0,0,1,1,1,0,1,0,0,0]=>2 [1,1,0,0,1,1,1,1,0,0,0,0]=>1 [1,1,0,1,0,0,1,0,1,0,1,0]=>4 [1,1,0,1,0,0,1,0,1,1,0,0]=>3 [1,1,0,1,0,0,1,1,0,0,1,0]=>2 [1,1,0,1,0,0,1,1,0,1,0,0]=>3 [1,1,0,1,0,0,1,1,1,0,0,0]=>2 [1,1,0,1,0,1,0,0,1,0,1,0]=>4 [1,1,0,1,0,1,0,0,1,1,0,0]=>3 [1,1,0,1,0,1,0,1,0,0,1,0]=>3 [1,1,0,1,0,1,0,1,0,1,0,0]=>3 [1,1,0,1,0,1,0,1,1,0,0,0]=>2 [1,1,0,1,0,1,1,0,0,0,1,0]=>2 [1,1,0,1,0,1,1,0,0,1,0,0]=>3 [1,1,0,1,0,1,1,0,1,0,0,0]=>2 [1,1,0,1,0,1,1,1,0,0,0,0]=>2 [1,1,0,1,1,0,0,0,1,0,1,0]=>2 [1,1,0,1,1,0,0,0,1,1,0,0]=>1 [1,1,0,1,1,0,0,1,0,0,1,0]=>2 [1,1,0,1,1,0,0,1,0,1,0,0]=>3 [1,1,0,1,1,0,0,1,1,0,0,0]=>2 [1,1,0,1,1,0,1,0,0,0,1,0]=>2 [1,1,0,1,1,0,1,0,0,1,0,0]=>3 [1,1,0,1,1,0,1,0,1,0,0,0]=>2 [1,1,0,1,1,0,1,1,0,0,0,0]=>2 [1,1,0,1,1,1,0,0,0,0,1,0]=>1 [1,1,0,1,1,1,0,0,0,1,0,0]=>1 [1,1,0,1,1,1,0,0,1,0,0,0]=>2 [1,1,0,1,1,1,0,1,0,0,0,0]=>2 [1,1,0,1,1,1,1,0,0,0,0,0]=>1 [1,1,1,0,0,0,1,0,1,0,1,0]=>3 [1,1,1,0,0,0,1,0,1,1,0,0]=>2 [1,1,1,0,0,0,1,1,0,0,1,0]=>1 [1,1,1,0,0,0,1,1,0,1,0,0]=>2 [1,1,1,0,0,0,1,1,1,0,0,0]=>1 [1,1,1,0,0,1,0,0,1,0,1,0]=>3 [1,1,1,0,0,1,0,0,1,1,0,0]=>2 [1,1,1,0,0,1,0,1,0,0,1,0]=>3 [1,1,1,0,0,1,0,1,0,1,0,0]=>2 [1,1,1,0,0,1,0,1,1,0,0,0]=>2 [1,1,1,0,0,1,1,0,0,0,1,0]=>1 [1,1,1,0,0,1,1,0,0,1,0,0]=>2 [1,1,1,0,0,1,1,0,1,0,0,0]=>2 [1,1,1,0,0,1,1,1,0,0,0,0]=>1 [1,1,1,0,1,0,0,0,1,0,1,0]=>3 [1,1,1,0,1,0,0,0,1,1,0,0]=>2 [1,1,1,0,1,0,0,1,0,0,1,0]=>3 [1,1,1,0,1,0,0,1,0,1,0,0]=>2 [1,1,1,0,1,0,0,1,1,0,0,0]=>2 [1,1,1,0,1,0,1,0,0,0,1,0]=>3 [1,1,1,0,1,0,1,0,0,1,0,0]=>2 [1,1,1,0,1,0,1,0,1,0,0,0]=>2 [1,1,1,0,1,0,1,1,0,0,0,0]=>2 [1,1,1,0,1,1,0,0,0,0,1,0]=>1 [1,1,1,0,1,1,0,0,0,1,0,0]=>2 [1,1,1,0,1,1,0,0,1,0,0,0]=>2 [1,1,1,0,1,1,0,1,0,0,0,0]=>2 [1,1,1,0,1,1,1,0,0,0,0,0]=>1 [1,1,1,1,0,0,0,0,1,0,1,0]=>2 [1,1,1,1,0,0,0,0,1,1,0,0]=>1 [1,1,1,1,0,0,0,1,0,0,1,0]=>2 [1,1,1,1,0,0,0,1,0,1,0,0]=>2 [1,1,1,1,0,0,0,1,1,0,0,0]=>1 [1,1,1,1,0,0,1,0,0,0,1,0]=>2 [1,1,1,1,0,0,1,0,0,1,0,0]=>2 [1,1,1,1,0,0,1,0,1,0,0,0]=>2 [1,1,1,1,0,0,1,1,0,0,0,0]=>1 [1,1,1,1,0,1,0,0,0,0,1,0]=>2 [1,1,1,1,0,1,0,0,0,1,0,0]=>2 [1,1,1,1,0,1,0,0,1,0,0,0]=>2 [1,1,1,1,0,1,0,1,0,0,0,0]=>2 [1,1,1,1,0,1,1,0,0,0,0,0]=>1 [1,1,1,1,1,0,0,0,0,0,1,0]=>1 [1,1,1,1,1,0,0,0,0,1,0,0]=>1 [1,1,1,1,1,0,0,0,1,0,0,0]=>1 [1,1,1,1,1,0,0,1,0,0,0,0]=>1 [1,1,1,1,1,0,1,0,0,0,0,0]=>1 [1,1,1,1,1,1,0,0,0,0,0,0]=>0
search for individual values
searching the database for the individual values of this statistic
/ search for generating function
searching the database for statistics with the same generating function
click to show known generating functions       
Description
The maximal torsionfree index of an indecomposable non-projective module in the linear Nakayama algebra corresponding to a Dyck path.
See the Nakayama algebras page for the correspondence between linear Nakayama algebras and Dyck paths.
Code
gap('LoadPackage("QPA");')

import tempfile as _tf, os as _os
_gap_code = r"""
DeclareOperation("NthRadical",[IsList]);
InstallMethod(NthRadical, "for a representation of a quiver", [IsList], 0, function(LIST)
    local M, N, f, h, i, n;
    M := LIST[1];
    n := LIST[2];
    if n = 0 then
        return(IdentityMapping(M));
    else
        f := RadicalOfModuleInclusion(M);
        N := Source(f);
        for i in [1..n-1] do
            h := RadicalOfModuleInclusion(N);
            N := Source(h);
            f := \*(h,f);
        od;
        return(f);
    fi;
end);

DeclareOperation("ARQuiverNak",[IsList]);
InstallMethod(ARQuiverNak, "for a representation of a quiver", [IsList], 0, function(LIST)
    local A, UU, i, injA, j;
    A := LIST[1];
    injA := IndecInjectiveModules(A);
    UU := [];
    for i in injA do
        for j in [0..Dimension(i)-1] do
            Append(UU,[Source(NthRadical([i,j]))]);
        od;
    od;
    return(UU);
end);

DeclareOperation("IsNtorsionfree",[IsList]);

InstallMethod(IsNtorsionfree, "for a representation of a quiver", [IsList],0,function(LIST)
    local A, CoRegA, M, i, n, temm23;
    A := LIST[1];
    M := LIST[2];

    n := LIST[3];

    CoRegA := DirectSumOfQPAModules(IndecInjectiveModules(A));
    temm23 := [];
    for i in [0..n-1] do Append(temm23,[Size(ExtOverAlgebra(NthSyzygy(CoRegA,i),DTr(M))[2])]);
    od;
    return(Sum(temm23));
end);

DeclareOperation("torsionfreeindex",[IsList]);

InstallMethod(torsionfreeindex, "for a representation of a quiver", [IsList],0,function(LIST)
    local A, M, U, g;
    A := LIST[1];
    M := LIST[2];
    g := LIST[3];
    U := Filtered([1..g],x->IsNtorsionfree([A,M,x])>0);
    return(Minimum(U)-1);
end);

DeclareOperation("torsionmax",[IsList]);

InstallMethod(torsionmax, "for a representation of a quiver", [IsList],0,function(LIST)
    local A, UU, g, i, simA;
    A := LIST[1];
    g := GlobalDimensionOfAlgebra(A,30);
    simA := Filtered(SimpleModules(A),x->IsProjectiveModule(x)=false);
    UU := [];
    for i in simA do Append(UU,[torsionfreeindex([A,i,g])]);
    od;
    return(Maximum(UU));
end);

DeclareOperation("torsionmaxall",[IsList]);

InstallMethod(torsionmaxall, "for a representation of a quiver", [IsList],0,function(LIST)
    local A, UU, WW, WW2, g, i;
    A := LIST[1];
    g := GlobalDimensionOfAlgebra(A,30);
    WW := ARQuiverNak([A]);
    WW2 := Filtered(WW,x->IsProjectiveModule(x)=false);
    UU := [];
    for i in WW2 do Append(UU,[torsionfreeindex([A,i,g])]);
    od;
    return(Maximum(UU));
end);
"""
with _tf.NamedTemporaryFile(mode="w", suffix=".g", delete=False, dir="/tmp") as _f:
    _f.write('LoadPackage("QPA");;\n')
    _f.write(_gap_code)
    _tmp = _f.name
gap.eval('Read("' + _tmp + '");')
_os.unlink(_tmp)

def kupisch(D):
    DR = D.reverse()
    H = DR.heights()
    return [1 + H[i] for i, s in enumerate(DR) if s == 0] + [1]

def statistic(D):
    K = kupisch(D)
    A = gap.NakayamaAlgebra(gap.GF(3), K)
    return ZZ(gap.torsionmaxall([A]))
Created
Nov 24, 2018 at 17:05 by Rene Marczinzik
Updated
Mar 13, 2026 at 15:03 by Nupur Jain