
// Make newform 3971.2.a.l in Magma, downloaded from the LMFDB on 14 January 2025.
// To make the character of type GrpDrchElt, type "MakeCharacter_3971_a();"
// To make the coeffs of the qexp of the newform in the Hecke field type "qexpCoeffs();"
// To make the newform (type ModFrm), type "MakeNewformModFrm_3971_2_a_l();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose lines below.
// The precision argument determines an initial guess on how many Fourier coefficients to use.
// This guess is increased enough to uniquely determine the newform.
// To make the Hecke irreducible modular symbols subspace (type ModSym)
// containing the newform, type "MakeNewformModSym_3971_2_a_l();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose line below.
// The default sign is -1.  You can change this with the optional parameter "sign".
function ConvertToHeckeField(input: pass_field := false, Kf := [])
    if not pass_field then
        poly := [3, 27, 30, -70, -38, 51, 12, -13, -1, 1];
        Kf := NumberField(Polynomial([elt : elt in poly]));
        AssignNames(~Kf, ["nu"]);
    end if;
    Rf_num := [[1, 0, 0, 0, 0, 0, 0, 0, 0], [0, 1, 0, 0, 0, 0, 0, 0, 0], [-3, 0, 1, 0, 0, 0, 0, 0, 0], [230, 842, -335, -949, 323, 290, -111, -24, 10], [-369, -1076, 301, 1022, 2, -278, -26, 22, 3], [176, 1135, -542, -1022, 569, 260, -170, -19, 14], [-360, -626, 1467, 511, -1134, -127, 288, 9, -22], [-206, -1102, 1084, 1387, -1138, -447, 340, 38, -28], [540, 1304, -2237, -1825, 1701, 592, -432, -50, 33]];
    Rf_basisdens := [1, 1, 1, 73, 73, 73, 73, 73, 73];
    Rf_basisnums := ChangeUniverse([[z : z in elt] : elt in Rf_num], Kf);
    Rfbasis := [Rf_basisnums[i]/Rf_basisdens[i] : i in [1..Degree(Kf)]];
    inp_vec := Vector(Rfbasis)*ChangeRing(Transpose(Matrix([[elt : elt in row] : row in input])),Kf);
    return Eltseq(inp_vec);
end function;


// To make the character of type GrpDrchElt, type "MakeCharacter_3971_a();"
function MakeCharacter_3971_a()
    N := 3971;
    order := 1;
    char_gens := [1806, 2168];
    v := [1, 1];
    // chi(gens[i]) = zeta^v[i]
    assert UnitGenerators(DirichletGroup(N)) eq char_gens;
    F := CyclotomicField(order);
    chi := DirichletCharacterFromValuesOnUnitGenerators(DirichletGroup(N,F),[F|F.1^e:e in v]);
    return MinimalBaseRingCharacter(chi);
end function;

function MakeCharacter_3971_a_Hecke(Kf)
    return MakeCharacter_3971_a();
end function;


function ExtendMultiplicatively(weight, aps, character)
    prec := NextPrime(NthPrime(#aps)) - 1; // we will able to figure out a_0 ... a_prec
    primes := PrimesUpTo(prec);
    prime_powers := primes;
    assert #primes eq #aps;
    log_prec := Floor(Log(prec)/Log(2)); // prec < 2^(log_prec+1)
    F := Universe(aps);
    FXY<X, Y> := PolynomialRing(F, 2);
    // 1/(1 - a_p T + p^(weight - 1) * char(p) T^2) = 1 + a_p T + a_{p^2} T^2 + ...
    R<T> := PowerSeriesRing(FXY : Precision := log_prec + 1);
    recursion := Coefficients(1/(1 - X*T + Y*T^2));
    coeffs := [F!0: i in [1..prec]];
    coeffs[1] := 1; //a_1
    for i := 1 to #primes do
        p := primes[i];
        coeffs[p] := aps[i];
        b := p^(weight - 1) * F!character(p);
        r := 2;
        p_power := p * p;
        //deals with powers of p
        while p_power le prec do
            Append(~prime_powers, p_power);
            coeffs[p_power] := Evaluate(recursion[r + 1], [aps[i], b]);
            p_power *:= p;
            r +:= 1;
        end while;    
    end for;
    Sort(~prime_powers);
    for pp in prime_powers do
        for k := 1 to Floor(prec/pp) do
            if GCD(k, pp) eq 1 then
                coeffs[pp*k] := coeffs[pp]*coeffs[k];
            end if;
        end for;
    end for;
    return coeffs;
end function;


function qexpCoeffs()
    // To make the coeffs of the qexp of the newform in the Hecke field type "qexpCoeffs();"
    weight := 2;
    raw_aps := [[0, 1, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 1, 0, 0, 0, 0, 0], [0, 1, 0, 0, 0, 0, 1, 0, 0], [0, 0, 0, 1, 1, 0, 0, 0, 0], [-1, 0, 0, 0, 0, 0, 0, 0, 0], [1, 0, 1, 0, -1, 0, 1, 0, 0], [-1, 0, -1, -1, 0, 1, 1, 1, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 1, 0, 0, 0, 0, 0, -1], [1, 0, 1, -2, -1, 0, 0, 0, -1], [3, 0, 1, 0, 2, 1, 0, -1, 1], [3, -1, 0, -1, 0, 1, 0, -2, 0], [1, -1, -1, 0, 1, 1, 2, 0, -1], [0, 2, 1, 0, -1, -1, -2, -2, 0], [1, 1, 0, 2, 0, 0, 0, 1, 0], [-1, 2, -1, -1, -2, 0, 2, 0, 1], [3, -2, 0, -2, -1, 0, 2, 1, -1], [1, 1, 0, -1, 1, 1, 1, -2, 1], [0, 1, -1, 0, 4, 1, -1, 2, 0], [-1, 2, 0, 1, 0, -1, -2, -2, -1], [3, -1, 0, 0, -2, 0, 2, -1, 0], [3, 2, 0, 0, -1, -1, -1, 0, 2], [2, 3, -1, 1, 0, 0, -2, -1, 1], [0, -1, 0, -1, 2, 1, 3, 0, 1], [3, 2, -1, -1, 0, -4, -3, -4, 0], [-4, -1, 1, 2, 1, 0, -1, 0, -1], [3, 3, -2, 0, 3, -1, -1, 0, 1], [3, -1, 3, 1, -1, 0, 0, 1, -1], [1, 4, -1, 0, -1, 0, 4, 0, 1], [-2, 1, -2, 2, 1, 0, 2, 4, 1], [-2, 1, 2, 0, 0, -3, -1, -3, 0], [3, -2, 3, 0, -2, -1, -2, -4, -2], [-1, -3, 1, 2, -3, 0, -3, 3, 0], [-3, -3, 1, -1, 0, 1, 3, 2, 0], [-1, -2, -5, -3, 5, 2, 1, 3, 1], [5, -2, 1, -1, -4, -2, -2, -1, -2], [-3, -1, 0, -3, -1, 2, -1, 1, 1], [-3, 5, 2, -3, 0, 2, 0, 1, 0], [7, 3, 3, 0, 0, 1, 3, -3, -1], [0, -5, -4, 0, 1, 0, -4, 3, 0], [3, 3, 1, -3, 0, -2, 0, -2, 0], [5, -3, -3, -1, -1, 2, 0, 0, 2], [3, 0, 0, 0, 1, 0, 1, 0, -1], [1, 3, 0, -3, 2, 2, 1, 2, 0], [3, 3, -3, 4, 1, -3, -2, 1, 0], [1, 0, -4, -4, 2, 3, 3, 3, 3], [7, 0, -1, 1, 3, 1, 2, 2, 0], [-5, 1, 0, 1, -3, -1, -2, 0, 0], [3, -3, 0, 1, 3, 0, 0, -2, 1], [-4, -2, -3, -1, -2, -1, -2, 1, -1], [-9, 2, -4, 1, 3, -2, 2, 2, 0], [0, -2, 3, -2, -1, -2, -1, -4, 0], [8, -3, 4, 0, 2, 5, 3, 1, 0], [4, 1, 2, 3, 0, -5, -4, -6, 0], [-7, -3, 1, 3, -3, -2, -4, 2, -4], [-6, 0, -3, -1, -4, -5, -4, 0, -2], [5, 6, -3, 1, 4, 0, -1, 2, 2], [6, 2, 0, -2, 2, -5, -4, -2, -1], [-1, 3, 2, 1, -1, -5, -2, -1, -5], [-1, 5, 4, 1, 3, -5, -3, 0, -3], [2, 1, -2, 0, 1, 3, 3, 0, 5], [8, -5, 1, -1, 2, 3, 3, 6, -2], [-5, 0, 8, 1, 1, -1, -6, -3, -4], [11, 3, -3, -6, -4, 0, -1, 1, 0], [3, 3, 0, 0, -3, 0, 10, 2, -1], [-2, -9, -4, 1, 0, 3, 6, 6, 0], [0, -1, -2, -10, 1, 0, -1, 0, 0], [9, -6, 1, 1, 2, 3, 1, -1, 0], [3, 7, 0, 3, 2, 1, 1, -5, 2], [1, 4, 3, -1, -4, 3, 3, 0, 1], [-5, 0, -2, -3, 1, -1, 2, 4, 1], [-3, -8, -1, 5, -3, -1, 1, 4, -1], [-5, -3, 2, -3, 2, 2, -7, 0, 0], [-2, -5, -1, 0, -1, 2, 7, 5, -2], [9, 0, 0, 5, 2, -5, -5, 1, 1], [-11, 2, -5, -1, -2, -3, -1, 1, -2], [-3, -6, 2, 0, 4, 0, -3, 0, -3], [4, -2, -1, 0, 9, 6, 0, 1, 0], [-5, -4, -2, 1, 4, -1, 4, 2, -1], [-2, 0, 2, -3, -2, 2, -3, 2, 1], [-8, 0, 1, -7, -1, -3, 1, 4, -3], [-4, -1, 5, -6, -2, 2, 7, 1, 2], [2, -5, 1, 4, 1, -5, -4, -3, 2], [10, 5, -4, 6, 6, 1, -3, 1, 2], [-2, -2, 7, 1, 0, -1, -6, 0, -4], [-9, -2, -4, -1, 1, 0, 2, 2, -4], [6, 6, 9, -1, -2, -1, -6, -5, -3], [-1, -10, 0, 5, 1, 0, 1, -1, 0], [-9, 1, 9, -1, -5, -3, 2, -1, -2], [9, -3, 3, 2, 6, 2, 1, 3, -2], [4, -10, 0, 2, 2, 2, 5, 6, 3], [9, 6, 1, 3, 0, -7, 2, -1, 1], [-6, -4, 1, -1, 4, 10, 2, 4, 3], [-1, -4, 1, 2, 3, 5, 1, -1, 2], [10, -7, -3, 1, 4, 5, 4, 7, 4], [-5, -1, 3, 3, -3, -3, -7, -7, 1], [-10, 7, 4, 6, -4, -2, -6, -4, -3], [4, -2, -1, 2, -2, -3, -2, -2, 0], [3, -2, 3, 2, 7, 7, 1, 1, -2], [3, -6, 1, 7, 3, -6, -7, -3, 1], [0, 1, -8, -3, 3, -5, -4, -1, -1], [-8, 1, 1, -1, -3, 4, 6, -1, 3], [5, -1, -6, -1, 7, 0, -7, 0, 0], [-8, 0, -3, -5, -7, 5, 13, 2, -1], [3, 7, 2, 5, -5, -6, 0, -8, 5], [-6, 3, -2, 4, 1, -1, 2, -1, 5], [4, 1, 2, -3, -3, 2, 1, 4, -2], [0, 2, -1, 5, -2, -2, -4, -3, 0], [0, -11, 3, -1, -4, 1, -5, 3, 1], [9, -1, -2, -3, -2, -2, 6, -1, 2], [0, 0, 2, 10, -4, -2, -4, 6, -2], [3, -3, 0, -3, -11, -3, -4, -4, -2], [9, 1, 3, -5, -5, -8, -7, -4, -5], [1, 2, 1, 0, 0, -5, 3, -7, -2], [-7, 3, -3, -2, 2, 0, -7, -2, -1], [-14, 13, 6, -1, -6, 0, 3, 1, -3], [-14, -1, 1, 7, 5, -2, 0, -3, 1], [5, -2, 4, 4, 1, 2, 7, -2, 3], [-5, 1, 4, 3, 4, 4, -6, 3, 0], [-1, 6, -2, 6, -3, -5, -4, 2, -1], [17, -5, 4, 4, -1, 0, -7, -6, -2], [14, -9, 1, 3, 0, 3, -9, 2, -2], [2, 1, -1, -4, -4, 1, 3, 7, 1], [5, -5, 6, 1, -6, 2, -5, -5, -1], [9, 2, -1, 0, 2, -3, -5, -1, 0], [1, 3, -2, 1, 3, 1, 2, 4, -4], [-8, -6, -6, 1, 3, 2, 8, 7, -1], [-1, -5, 0, -9, -7, 5, 8, 0, 2], [3, 5, -2, -10, 1, 1, 8, 5, -1], [11, 0, -10, 5, 9, -2, -4, 3, 1], [-4, 2, 5, 2, 3, -7, -11, -8, -1], [-19, -1, -6, 1, 0, -1, 1, 7, 2], [-1, -8, -2, 5, -3, -8, -4, 2, -6], [-11, 8, 4, -5, -2, -3, 1, -4, -2], [9, 0, 6, 1, 2, 7, -6, -1, 0], [9, 0, -2, 0, 6, -1, 4, 1, 2], [8, 2, -6, 6, 7, -1, -6, -3, 0], [9, 0, 8, 5, -6, -2, 0, -2, -2], [-10, 1, 4, -1, -3, -7, -3, -4, -1], [7, 2, 1, 0, -1, -2, 3, -9, -1], [16, -7, 3, 2, -3, -1, -1, -5, 3], [-1, -6, -9, 1, 4, 5, 4, 7, -5], [9, 10, -2, 1, 1, -2, 4, -2, 2], [-11, 4, 5, -1, 2, 3, 1, 1, 2], [24, -4, -5, 3, 6, 4, -4, 2, 3], [-15, -7, 8, 4, -9, 1, -2, -1, -3], [-3, 1, 4, -4, -3, -3, 1, 1, -4], [0, 5, 3, -4, 0, 1, 9, 0, 6], [-13, 2, 0, -2, 6, -1, -3, 9, -3], [-8, 7, 1, -2, -4, 1, 1, 1, -3], [8, 8, 2, -1, 0, -4, 4, 0, 0], [-13, 12, -8, -5, -3, -8, -6, -3, -3], [5, -9, 5, 8, -2, -2, -12, 0, -6], [1, -1, -1, -7, -4, 5, -4, 0, -5], [-5, 3, 0, 10, 5, -3, -8, -5, 1], [0, -8, -2, 10, 7, -5, -9, -4, 0], [-1, 5, 0, 3, -3, -4, -7, -4, 4], [-4, -1, 2, -5, 0, -3, -2, -4, -2], [-3, -2, 6, 5, 5, 4, 2, 2, -4], [2, 3, -3, 2, -6, 1, 0, 4, 5], [-16, 1, -4, 7, 4, 3, 6, 2, 0], [4, 5, -2, -7, -5, -6, -10, -2, -5], [-5, -6, -1, 11, 3, 1, -1, 10, 3], [-8, -3, 0, 5, 1, 0, -1, -2, 2], [-2, 17, 4, 3, 5, -1, 4, -8, 0], [-2, 3, -1, -7, -6, 3, 2, 1, -2], [-15, -8, 8, 0, -1, 2, -8, -3, -3], [5, 11, -2, -2, 1, -9, -8, -5, -1], [-8, 3, 3, -10, -9, -4, 1, -2, -3], [-10, 14, -1, -2, -1, -4, -11, -5, 1], [11, -6, -7, -10, -14, -2, 3, -2, 2], [11, -8, 4, -4, -8, 0, -4, -2, -2], [20, -1, -2, -10, -4, -1, 0, -1, 3], [4, -3, -3, -13, -6, 1, 6, 4, -5], [1, 15, 0, -6, 3, -7, -1, -1, -4], [16, 1, -2, -11, 6, -2, 3, 1, -1], [4, 5, -8, -10, 5, 1, 0, 4, 2], [-1, -7, 1, -13, -9, -3, 2, 3, -6], [17, 6, -1, -2, 0, 10, 15, 4, 2], [-4, 2, -4, -17, -9, 3, -1, -2, -4], [-1, 12, 5, 0, -12, 3, 2, 0, 2], [-8, -2, -1, 1, 13, 8, 6, 11, 4], [10, 4, 6, 4, -1, 1, 2, -7, 0], [-4, 8, -3, 0, -5, 3, 3, 4, 7], [-2, -3, 6, 2, -8, 3, -8, 4, 2], [4, 3, 4, 6, -3, -9, -4, -7, -9], [9, -11, 1, -1, 2, 4, 12, 13, 1], [11, 0, 4, -2, -7, -2, 2, -5, -3], [10, 9, -6, 3, 3, -2, -5, 1, 1], [5, -7, -12, 5, 8, 4, 7, 7, 9], [6, -10, 0, 10, 1, -2, -6, 6, 6], [24, 9, -2, 0, -1, 1, -3, -8, 1], [2, -1, -6, -6, 6, 5, 7, 4, 1], [7, -11, -7, 10, -1, -2, 10, 7, -1], [-2, 5, -8, 3, 13, -1, -2, -5, 1], [2, -6, -5, -4, 5, 6, 3, 3, 1], [16, -1, 8, -1, 2, 9, 2, 0, 4], [3, 2, -4, -4, 6, 7, 0, -1, 8], [-6, -5, -1, -9, -5, -2, 2, 4, 4], [-7, -3, 10, -6, 10, 4, -5, 2, -2], [12, 10, -7, -9, 5, 5, 0, 5, 1], [-5, 1, 9, -7, -6, -5, -1, -12, -4], [12, 2, -6, -10, -5, 0, 2, -6, 6], [18, -9, 1, -3, -4, -1, 6, -3, -2], [-6, 0, 1, 8, 6, -4, -12, -2, -3], [3, 9, 1, -2, 3, 13, 7, 2, -2], [4, 9, -8, 7, 1, -8, -10, -6, -3], [-16, -1, 6, -9, -5, 9, 1, 1, 4], [15, -6, 7, -3, 6, 3, 1, 9, -4], [-3, 14, -4, 7, 3, 0, 0, 5, -7], [-5, 6, 4, -12, -5, 6, -3, 1, 6], [4, -3, -3, -1, -6, -11, 5, -1, -5], [1, -7, 1, 15, 1, -3, 3, -2, -4], [-3, 3, 12, 8, -2, -6, -9, -7, -5], [-1, -5, 8, -2, -9, -4, -13, -11, -3], [8, 0, -6, 5, 11, 2, -8, 3, 9], [-20, 8, -1, 1, 0, 1, -2, 0, 0], [5, 2, -9, 7, 10, -5, -6, 6, 0], [9, -11, 4, 7, 7, 1, -9, 5, 0], [-21, -14, 2, -5, -6, 11, 4, 6, 1], [6, 2, -3, 9, 15, 1, 5, 5, -6], [10, 11, -4, -1, 0, 0, 9, 2, -2], [-3, -3, -5, 7, 1, -3, 4, -5, 2], [2, -7, -2, 5, 8, 7, -3, 6, -3], [15, 9, 3, 7, 4, -11, -6, -4, -5], [-8, 2, 5, 0, 8, 12, 16, 4, 7], [10, -2, 0, -8, -8, 8, 20, 14, 0], [-20, -9, 1, 2, 0, 1, 4, 8, 3], [-1, 1, 1, 8, 6, 3, -6, 1, 4], [21, -3, -2, -11, 3, -4, -11, 0, 2], [30, -1, 1, -4, 6, 2, -4, -3, 7], [24, -3, -3, -2, 2, -7, -8, -2, 3], [-11, 6, -5, -5, -11, -4, 11, 6, -2], [-12, 9, 4, -4, -9, -6, -10, -10, 7], [13, 4, 2, 1, 5, 2, -8, -5, 1], [36, 1, 0, 1, -2, -7, 4, 0, 2], [-16, -7, 10, 9, -5, -8, -5, -5, 1], [6, -10, -3, -9, -10, 4, 10, 4, -1], [-10, 4, -7, -10, -1, 7, 5, 10, 1], [-17, -7, -5, -2, 5, 3, 4, -6, 5], [3, 1, -3, -2, -6, -6, 0, -2, -2], [4, 0, -2, -11, 1, 4, -11, -12, -1], [-26, 6, 8, 2, -5, -5, -3, -5, -7], [24, 9, -3, -3, -4, 0, 8, -2, 0], [14, 1, -2, -9, 11, 10, 2, 2, 3], [13, 7, -11, -1, 9, -2, -10, -1, 3], [-4, 7, -4, -12, -5, -2, -12, -5, -4], [-7, 6, -3, -7, -7, 6, -2, -3, 8], [-6, 3, -2, -12, 1, 15, 12, 10, 6], [16, -3, -5, -1, 3, 5, -1, 0, -2], [-8, -17, 8, 7, -11, -2, -2, 3, -6], [-27, -2, 0, 4, 2, 1, 10, 11, 0], [6, -8, 11, 7, 5, 11, 10, 0, 2], [-2, 8, 4, -6, -3, -8, -12, -14, -4], [5, -11, -1, 10, 10, -2, -5, 6, 1], [-11, 2, -4, 11, 6, -3, -3, 4, -2], [-9, -4, 3, -2, -10, -5, 1, -2, -5], [-3, -5, 9, -14, -6, 2, 8, 1, 3], [6, 12, 15, -5, 5, 0, 3, -8, 2], [-3, -5, 9, 12, -1, 1, -16, -6, -3], [-1, 4, -3, -11, -11, 7, 7, 4, -1], [-19, -15, 1, 8, 5, -3, 5, 6, -2], [-1, 0, -9, 9, 8, -5, -3, 1, 2], [-4, 2, -1, -2, -2, 6, 6, -6, -1], [-4, 3, 8, -2, -14, -10, -1, -8, 2], [18, -8, -2, 6, 14, 4, 5, 2, 1], [-5, -10, 0, 0, -5, -7, -5, -5, -1], [-27, -10, -1, -2, -5, 0, 3, 7, -5], [-15, -1, -3, 13, 3, 5, -6, 1, 8], [12, 4, -3, -6, 4, 16, 11, 10, 6], [-2, 2, 10, -12, -12, -10, -15, -16, -1], [13, -1, 1, 18, 5, -13, -8, 5, -4], [13, 0, -7, 6, 4, -6, 6, 1, 0], [7, 0, 14, 5, -8, 6, 14, 0, 4], [12, 7, 3, 10, 3, -6, -1, 8, -9], [1, -12, 7, 0, 4, 5, -7, -6, -1], [10, -4, 3, -13, -6, 4, 17, 8, -2], [25, -11, -3, 1, 10, -8, -11, -7, -2], [39, 12, 0, 1, -2, -1, 0, -14, 1], [-25, 5, 0, 4, -2, -1, -7, 4, 7], [15, 9, 5, -7, -9, 2, -6, -5, 5], [-6, -16, -11, 6, 6, 0, 0, 5, 0], [-7, 2, -8, 0, 11, 11, 8, 12, 7], [5, -2, -11, 6, 7, -2, -5, 3, 7], [17, -13, -5, 7, 8, -7, -1, 0, -2], [-4, -9, -8, 4, 0, 3, 12, 5, -1], [-14, -13, 9, 0, -15, -8, -8, -7, -1], [-9, 8, -11, 0, 3, 0, -1, 6, -4], [8, 19, 6, -3, 3, 8, 16, -4, 5], [25, -7, -6, -1, 0, 6, 1, 7, 3], [-5, -2, 3, 6, 3, -4, 10, -5, -6], [-13, -11, 3, 2, -8, 10, 10, 1, 1], [6, -5, 1, 9, -5, 8, -3, 11, 0], [30, -6, 5, -9, -6, 2, 0, -4, 3], [16, -1, -14, -1, -6, 1, 1, 6, -1], [9, 3, -5, 6, -2, -4, 11, 5, 6], [-32, 2, -6, 0, 1, -7, 0, 5, -6], [19, -2, -12, -3, 0, -11, 2, -6, -1], [9, -18, 5, 7, -1, -1, -9, -6, -1], [17, 1, 4, -12, -9, 4, 1, -5, -1], [25, -3, 10, -12, -8, 4, 8, -1, 2], [-9, 8, -10, 3, -13, -10, -2, 2, -8], [-5, -23, -5, -3, 4, 3, -7, -2, 6], [-4, -10, 5, 9, -4, 2, -12, -6, -3], [10, 9, -5, -2, -13, -4, 3, -8, 5], [7, -4, -3, -10, -12, 1, -1, -6, 9], [-10, 17, -2, -2, -1, 4, 23, -3, 7], [13, 9, 9, 14, -5, -6, -8, -7, -5], [6, -7, 5, -7, -4, 11, 13, 13, -3], [5, 6, -3, 3, 1, -6, 3, -12, 4], [4, 15, 5, -12, 5, 18, 12, -1, 3], [12, -11, -4, -11, 2, 2, 3, 3, -1], [6, -5, 0, 7, 1, 0, 8, -2, 3], [-26, -8, -11, -18, -8, 10, 13, 19, -3], [-13, 12, -10, -6, -6, -1, 2, 9, 2], [-15, 3, -12, 4, -10, -10, -5, 4, -6], [-15, 9, 12, 3, -20, -12, -1, -6, -4], [7, -4, 3, -1, -13, 3, 7, -8, 1], [-6, -15, -4, 3, 12, 9, 10, 2, 8], [19, -10, -1, -11, -8, -5, 4, 4, 0], [17, 11, 4, 6, -10, -5, -12, -12, -4], [36, 14, -10, -1, 3, 2, 1, 3, 0], [14, -8, 4, 1, -3, 13, 16, 12, 3], [-7, -7, 12, 5, -10, 2, -13, -6, -6], [-2, -8, 7, 9, 2, 4, -4, -9, 2], [6, 13, -9, -4, 4, -8, 7, 1, 4], [-21, -5, -9, -1, 7, 5, -10, -1, 8], [16, 7, -13, 3, 2, 9, 12, 6, 3], [-5, -7, -7, -15, -7, 13, 9, 15, -5], [4, -8, -2, 9, 2, 4, -10, 6, 8], [-1, 8, -2, -11, -17, -4, -9, -6, -5], [17, -11, -8, 9, 11, -2, -10, 11, 0], [7, 9, -2, 2, 11, 1, -6, -5, 3], [9, -2, -6, 6, 9, -12, -19, -12, 3], [13, 0, -1, 13, 5, 11, -3, -2, 5], [-24, 13, 0, -2, 3, 0, 0, 1, -2], [13, -23, 5, 9, 4, 7, -3, -5, 5], [-12, -2, -11, -22, -5, 9, 5, 11, -6], [-2, 24, 4, -6, -4, -7, 5, -3, -9], [4, 2, -10, 3, 13, 2, -2, 12, 0], [32, 6, 13, 8, -3, 1, 8, -4, -4], [3, -16, 6, 10, 6, 0, -9, -8, 1], [40, -4, 1, -3, -9, -11, -3, -3, -8], [-14, 16, 7, -3, -8, 4, 12, -2, -1], [-17, -3, -8, -9, 3, -6, 1, 5, -3], [4, 18, -4, 4, 21, -3, 5, 3, 3], [-13, 2, -1, 13, 16, 3, -2, 1, 5], [-10, -6, 13, -1, -5, 3, 8, 13, -3], [-7, 13, 4, -12, 4, 1, -14, -4, -2], [-23, 16, 0, -5, -5, 9, 18, 6, 7], [3, 10, -5, 5, -8, -5, 12, -11, -3], [13, -14, -7, -7, 12, 6, 15, 8, -6], [35, -24, 3, 10, 10, 8, 7, 7, -5], [2, -6, -11, -1, 3, 10, 3, -1, 9], [8, 5, -2, -1, -21, -12, -4, 10, -5], [-21, 1, -4, 11, 0, -2, 10, 9, -8], [16, -6, 0, 2, -1, 5, -6, 3, 0], [-31, -5, -12, -3, -4, 3, -3, 7, 0], [16, 1, 7, 23, 5, -8, -7, -1, -8], [-5, -11, -14, 11, 1, -7, -12, 0, -6], [7, 8, 2, -4, 4, 13, -10, -5, 0], [13, 1, 10, 5, 7, -9, -3, -14, 1], [-18, 1, 7, 17, -4, -1, -5, 1, 1], [-7, 8, -11, -1, 2, -4, -5, -1, -9], [-25, -14, 0, 4, -1, -4, -5, 15, -10], [11, 4, 10, 2, -2, -12, -8, -8, -6], [-15, -11, 7, -12, -7, 7, 7, 19, 1], [-3, -5, -8, -24, 0, 5, 21, 0, 3], [-2, 2, -12, -9, -2, 6, 2, -6, 2], [-11, -1, 6, -6, -18, -6, 2, -7, -8], [6, -5, -6, -3, 4, 1, 5, 11, 6], [18, 18, 15, 13, -14, -11, 4, -10, -2], [16, -16, -6, 8, 5, -7, -15, 3, -3], [-10, -4, -10, -9, 16, 9, -3, 15, 3], [11, -8, -10, -7, 9, 2, 1, 13, 4], [28, 6, -4, 5, 3, -1, -5, -6, 6], [10, 15, 2, -2, -2, -4, 13, -1, 1], [1, -4, 13, -5, -9, 0, 13, -13, -9], [-6, 15, -10, 10, 3, 2, -2, 15, -2], [-8, -3, -3, 0, 5, 14, 16, 14, 6], [10, 11, 0, -8, 9, 3, -5, -9, 8], [22, 2, 16, -8, -4, 9, -1, -3, -1], [12, 22, 6, -4, -4, 1, -6, -10, -3], [15, 1, -7, 5, -5, 1, 1, 3, 9], [20, -1, 5, -1, 23, 4, -3, 2, 1], [0, -23, -8, 0, 14, 9, 10, 3, 3], [-24, 3, -10, -2, 12, 9, 24, 18, 8], [2, -17, -2, 1, 2, -1, -9, -6, -5], [4, 9, 14, 1, 1, -11, -11, -3, 2], [-20, 5, 6, -6, -1, 4, 1, -12, 0], [11, -1, -8, 11, 3, 11, -1, 12, 1], [20, -19, 8, 11, -4, 4, -18, -11, -2], [8, -7, -8, 0, 15, -4, -10, -6, -3], [13, 3, -7, -1, 8, 4, -23, 7, 4], [-27, -1, 0, -13, -6, -4, -4, -2, -5], [15, 1, 4, -4, 3, -9, -9, -3, -4], [13, 2, -6, -12, -14, 7, 24, 1, 6], [-19, -4, -8, -1, 7, 8, 9, 11, -2], [10, 5, 5, -3, 6, 9, -4, -9, 4], [-14, 5, -6, 2, 7, -6, -14, 1, 2], [21, -18, -2, -2, -9, -2, 3, 9, 6], [8, -26, -9, 18, 3, -9, -8, -2, 2], [-20, -4, 8, 17, -1, -10, -3, -2, -3], [-14, -9, -4, 4, -2, 2, 5, 2, -2], [-7, -22, -10, -2, 14, 13, 4, -3, 6], [-21, 14, 2, 15, 7, -1, -4, 7, 0], [-4, -10, 19, 23, -1, -2, 0, -12, -9], [11, 13, 1, 14, -1, -11, -17, -23, -1], [9, 10, 5, 2, 10, -11, -17, -14, 1], [19, -7, 0, 2, 13, 3, -16, 10, -4], [-21, -4, 10, 15, 11, -2, -21, -4, 3], [-19, 10, -19, -1, -1, -8, 4, 7, 4], [5, -15, 15, -1, 12, 2, -10, 2, -6], [-3, -13, -3, 0, 13, 0, -20, -4, -4], [-33, 9, 4, 18, 1, -1, -16, -8, -2], [13, 12, 7, 16, -5, -13, -19, -22, -7], [-16, -14, 18, 4, 0, -5, -4, -6, -11], [2, -1, -17, -10, 14, 7, 3, 5, 7], [-1, -15, -10, 10, -1, -20, -10, 6, 3], [1, 7, -3, 21, 12, 3, 7, 2, 16], [-22, -5, 16, -2, 8, 2, -12, -8, -1], [-19, -9, 11, 2, -4, 4, -11, 2, -9], [-19, -18, -6, 2, 2, 9, -7, -6, 2], [-1, -6, 3, 4, -9, -3, -4, 11, -3], [11, -12, 6, -7, -3, -12, -5, -5, -14], [6, -10, -4, -9, -6, -9, 2, -12, 7], [-16, 4, -3, 14, 0, -6, 2, 15, -2], [-52, 2, 1, 4, -1, -1, 6, -2, 2], [7, -2, 16, 7, 6, 1, -8, -9, -4], [-10, -21, 5, -11, 9, 1, -8, 6, -7]];
    aps := ConvertToHeckeField(raw_aps);
    chi := MakeCharacter_3971_a_Hecke(Universe(aps));
    return ExtendMultiplicatively(weight, aps, chi);
end function;


// To make the newform (type ModFrm), type "MakeNewformModFrm_3971_2_a_l();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose lines below.
// The precision argument determines an initial guess on how many Fourier coefficients to use.
// This guess is increased enough to uniquely determine the newform.
function MakeNewformModFrm_3971_2_a_l(:prec:=9)
    chi := MakeCharacter_3971_a();
    f_vec := qexpCoeffs();
    Kf := Universe(f_vec);
    // SetVerbose("ModularForms", true);
    // SetVerbose("ModularSymbols", true);
    S := CuspidalSubspace(ModularForms(chi, 2));
    S := BaseChange(S, Kf);
    maxprec := NextPrime(2999) - 1;
    while true do
        trunc_vec := Vector(Kf, [0] cat [f_vec[i]: i in [1..prec]]);
        B := Basis(S, prec + 1);
        S_basismat := Matrix([AbsEltseq(g): g in B]);
        if Rank(S_basismat) eq Min(NumberOfRows(S_basismat), NumberOfColumns(S_basismat)) then
            S_basismat := ChangeRing(S_basismat,Kf);
            f_lincom := Solution(S_basismat,trunc_vec);
            f := &+[f_lincom[i]*Basis(S)[i] : i in [1..#Basis(S)]];
            return f;
        end if;
        error if prec eq maxprec, "Unable to distinguish newform within newspace";
        prec := Min(Ceiling(1.25 * prec), maxprec);
    end while;
end function;


// To make the Hecke irreducible modular symbols subspace (type ModSym)
// containing the newform, type "MakeNewformModSym_3971_2_a_l();".
// This may take a long time!  To see verbose output, uncomment the SetVerbose line below.
// The default sign is -1.  You can change this with the optional parameter "sign".
function MakeNewformModSym_3971_2_a_l( : sign := -1)
    R<x> := PolynomialRing(Rationals());
    chi := MakeCharacter_3971_a();
    // SetVerbose("ModularSymbols", true);
    Snew := NewSubspace(CuspidalSubspace(ModularSymbols(chi,2,sign)));
    Vf := Kernel([<2,R![3, 27, 30, -70, -38, 51, 12, -13, -1, 1]>,<3,R![-14, 148, 35, -224, -18, 110, 1, -19, 0, 1]>],Snew);
    return Vf;
end function;