
// Make newform 290.2.k.b in Magma, downloaded from the LMFDB on 01 May 2026.
// To make the character of type GrpDrchElt, type "MakeCharacter_290_k();"
// To make the character of type GrpDrchElt with Codomain the HeckeField, type "MakeCharacter_290_k_Hecke();"
// To make the coeffs of the qexp of the newform in the Hecke field type "qexpCoeffs();"
// To make the newform (type ModFrm), type "MakeNewformModFrm_290_2_k_b();".
// 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_290_2_k_b();".
// 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 := [1, 1, 2, 3, 5, 8, 13, -8, 5, -3, 2, -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, 0, 0], [0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [8, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0], [0, 21, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0], [0, 0, -21, 0, 0, 0, 0, 0, 0, -1, 0, 0], [0, 0, 34, 0, 0, 0, 0, 0, 0, 1, 0, 0], [0, 0, 0, 34, 0, 0, 0, 0, 0, 0, 1, 0], [0, 0, 0, -55, 0, 0, 0, 0, 0, 0, -2, 0], [0, 0, 0, 0, -55, 0, 0, 0, 0, 0, 0, -2], [0, 0, 0, 0, -89, 0, 0, 0, 0, 0, 0, -3], [3, 3, 6, 9, 15, -65, 39, -24, 15, -9, 6, -3], [8, 16, 24, 40, 64, 104, -65, 40, -24, 16, -8, 8]];
    Rf_basisdens := [1, 1, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13];
    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_290_k();"
function MakeCharacter_290_k()
    N := 290;
    order := 7;
    char_gens := [117, 31];
    v := [7, 5];
    // 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;

// To make the character of type GrpDrchElt with Codomain the HeckeField, type "MakeCharacter_290_k_Hecke();"
function MakeCharacter_290_k_Hecke( : Kf := false)
    N := 290;
    order := 7;
    char_gens := [117, 31];
    char_values := [[1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0]];
    assert UnitGenerators(DirichletGroup(N)) eq char_gens;
    values := ConvertToHeckeField(char_values : pass_field := ISA(Type(Kf), Fld), Kf := Kf); // the value of chi on the gens as elements in the Hecke field
    F := Universe(values);// the Hecke field
    chi := DirichletCharacterFromValuesOnUnitGenerators(DirichletGroup(N,F),values);
    return chi;
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, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0], [0, 0, -1, 0, 0, 1, 0, -1, 0, 0, 1, -1], [0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0], [0, -1, -1, -1, -1, 0, 1, 0, 1, 1, 1, 1], [0, -1, -1, 0, -1, 3, -1, 0, 1, 0, 0, 0], [0, 0, 0, -1, -2, -1, 0, 1, 0, 0, 0, 0], [-1, 0, 1, -2, 0, 0, 2, 0, -2, 0, 0, 2], [2, 1, 3, 1, -3, 2, 0, 0, -2, 0, -2, 0], [0, 0, 0, 0, 3, 0, -2, 2, 3, 0, 0, 0], [1, 0, 1, 2, 1, 0, -3, 1, -2, -2, -1, -2], [1, -1, -1, 1, 0, 2, -2, 0, 6, 0, 2, -2], [3, 0, 1, 0, 0, 0, 1, -3, 0, -3, -2, -3], [2, 0, -6, 2, 3, 0, -3, -2, 3, -2, 3, -2], [0, -5, 0, 0, 5, -2, -3, -1, 5, 2, 5, 0], [0, 2, 0, 3, -2, 2, 2, -3, 0, 0, 0, 0], [0, -2, -2, 0, 0, 5, -3, 0, 2, 3, 3, -5], [8, 0, 1, 1, 0, 0, 2, -2, -2, -2, 0, -1], [0, -4, -4, -2, 7, 3, -7, -3, 4, 2, 4, -6], [-2, 2, 3, -2, -2, -2, 3, 2, 0, 5, -4, 5], [1, 0, 3, -4, -2, -2, 0, 4, -3, -1, 0, 0], [4, -1, 0, 0, 4, -2, 3, -6, 4, 2, 1, -4], [0, 3, 7, -1, -3, -1, 7, 0, 0, 4, -2, 4], [-7, -1, 2, -8, -2, -7, 0, 5, -1, 0, -1, 5], [-3, 3, 3, -3, 0, -2, 0, 0, -10, -8, 0, 2], [-2, -5, -3, 4, 3, -2, 0, -7, -2, 0, -2, -7], [-7, 6, 0, 0, -1, 0, 7, -2, -1, 0, -6, 7], [8, 7, 7, 5, -5, 5, 7, -5, -7, -8, 0, 0], [-3, -2, -7, 3, 2, 3, -7, 3, 0, 2, 0, 2], [0, -3, 1, -5, -4, -4, 4, 4, 3, 5, -1, 5], [0, 3, 2, -5, -5, -1, 5, 1, -3, 5, -2, -3], [-1, 6, 2, 5, -4, 1, 6, -5, -2, 1, 0, 0], [-1, -2, 0, 0, 3, -8, -4, 2, 3, 8, 2, 1], [6, 0, 4, 2, 0, 2, 4, -6, 0, -1, 1, -1], [-2, -3, 0, 0, 2, -9, -5, 4, 2, 9, 3, 2], [1, -3, -5, -6, 5, 1, 0, 3, -2, 0, -2, 3], [4, -2, 0, 0, -4, 0, 0, -4, -4, 0, 2, -4], [-1, 0, -8, 1, -1, 0, -1, -1, 1, -1, -1, -1], [5, -3, 7, 3, -5, 7, -3, -3, -7, -5, 0, 0], [0, 9, 8, 6, -3, 0, 3, 0, -9, -6, -8, -1], [-6, 0, -1, 2, -7, 0, -1, 6, 1, 6, -7, -2], [-11, -1, -1, -11, 0, -4, -2, 0, -1, -2, 2, 4], [0, 3, 3, -5, -2, -5, 2, 5, -3, 5, -3, 15], [4, 0, -1, 11, 1, 0, 3, -10, -3, -10, 1, -11], [5, 4, 8, 4, -8, 5, 0, 9, -2, 0, -2, 9], [8, -7, 0, 0, 3, 1, -1, 6, 3, -1, 7, -8], [2, 12, 2, 6, -2, 2, 0, -4, -1, 0, -1, -4], [10, 6, 8, 5, -6, 5, 8, -10, 0, -5, -5, -5], [-10, -3, -3, -7, 3, -7, -3, 10, 0, -2, 7, -2], [-13, 7, 7, -13, 0, -10, 8, 0, 2, 7, -8, 10], [0, 10, 2, 5, 2, -11, -2, 11, -10, -5, -2, -8], [3, 0, -7, 4, 11, 0, 0, -7, 0, -7, 11, -4], [0, -5, -8, 5, 12, -10, -12, 10, 5, -5, 8, 6], [-2, -6, -3, -8, 6, -8, -3, 2, 0, 13, 0, 13], [-3, -6, -8, -1, 8, -3, 0, -6, 6, 0, 6, -6], [-1, -3, -4, -18, 4, -1, 0, -4, 4, 0, 4, -4], [-7, 5, 5, -7, 0, -3, 4, 0, 3, 11, -4, 3], [-13, -3, -2, -2, 3, -2, -2, 13, 0, 13, 3, 13], [-10, 5, 2, 10, -2, -10, 0, 6, -2, 0, -2, 6], [10, -9, -6, -3, 12, -1, -9, 3, 6, -10, 0, 0], [-3, 3, 4, -5, -3, -5, 4, 3, 0, 3, 0, 3], [0, -5, -10, -6, 8, 0, -8, 0, 5, 6, 10, -14], [0, -16, -8, 8, 14, 3, -14, -3, 16, -8, 8, -18], [-8, 0, -13, -4, 1, 0, -7, 4, 7, 4, 1, 4], [-7, 3, 8, -1, -3, -1, 8, 7, 0, 12, -12, 12], [-1, 4, 0, 0, 5, -11, -6, 4, 5, 11, -4, 1], [10, 3, 3, 10, 0, 3, -6, 0, 3, 5, 6, -3], [-2, 0, -1, -13, -4, 0, 5, -1, -5, -1, -4, 13], [-6, 4, 2, -4, -5, 2, 4, 4, -2, 6, 0, 0], [9, 0, 3, 12, -1, 0, -7, -6, 7, -6, -1, -12], [2, 0, 9, 0, -5, 0, -1, 1, 1, 1, -5, 0], [12, 7, 7, 12, 0, -6, 1, 0, 11, -2, -1, 6], [14, -6, -8, 6, 1, 25, -6, -6, 8, -14, 0, 0], [11, 10, 2, 9, -2, 11, 0, -3, -1, 0, -1, -3], [-3, 3, -10, -1, 10, -3, 0, -2, 7, 0, 7, -2], [-4, -12, -12, -4, 0, -5, 1, 0, 1, 10, -1, 5], [-14, 17, 0, 0, -5, -6, 10, -6, -5, 6, -17, 14], [17, 0, 5, 3, 10, 0, 3, -4, -3, -4, 10, -3], [-9, 4, -5, -9, -4, -9, -5, 9, 0, -3, -7, -3], [-8, -4, -4, -8, 0, -7, 3, 0, -16, 2, -3, 7], [0, 8, 15, -7, -22, 0, 22, 0, -8, 7, -15, 7], [12, 0, 3, 0, -5, 17, 0, 0, -3, -12, 0, 0], [7, -8, 0, 0, -1, 2, -17, -1, -1, -2, 8, -7], [8, -4, 8, -2, -8, 8, 0, -12, 1, 0, 1, -12], [11, 0, 0, 11, 0, 11, 3, 0, -5, -1, -3, -11], [0, 2, -4, -17, 4, 0, 0, -1, -1, 0, -1, -1], [-23, -7, -6, -18, 7, -18, -6, 23, 0, 12, 1, 12], [7, -9, 0, 0, -2, 18, 7, -12, -2, -18, 9, -7], [0, -6, -7, 3, 15, -6, -15, 6, 6, -3, 7, 4], [0, -2, -12, 3, -5, 10, 5, -10, 2, -3, 12, 2], [14, 0, 12, 7, -5, 0, 10, -10, -10, -10, -5, -7], [0, 14, 18, -7, -16, -2, 16, 2, -14, 7, -18, 5], [-10, -3, 0, 0, 3, -11, 2, -4, 3, 11, 3, 10], [0, -8, 0, 0, -6, 8, 8, 3, -6, -8, 8, 0], [0, 3, 3, 0, 0, -1, 0, 0, 14, 20, 0, 1], [-5, 4, 0, 0, 3, 9, 8, -5, 3, -9, -4, 5], [5, 5, -3, 11, 3, 5, 0, -1, 2, 0, 2, -1], [6, -6, 1, -2, 13, 7, -6, 2, -1, -6, 0, 0], [26, 0, -1, 13, 12, 0, -6, -6, 6, -6, 12, -13], [-2, 0, -26, 3, 3, 0, -1, -2, 1, -2, 3, -3], [-8, -11, -3, -7, 3, -8, 0, -2, -11, 0, -11, -2], [5, -7, 10, -15, -10, 5, 0, -10, -6, 0, -6, -10], [3, 8, 0, 0, -6, -2, 2, -2, -6, 2, -8, -3], [-1, 0, 25, -10, -13, 0, 9, 1, -9, 1, -13, 10], [2, -10, -9, -11, 15, 6, -10, 11, 9, -2, 0, 0], [-5, -14, 0, -18, 14, -18, 0, 5, 0, 0, 15, 0], [0, 13, 8, 3, -6, -12, 6, 12, -13, -3, -8, 13], [0, 5, 17, -2, -6, -9, 6, 9, -5, 2, -17, 3], [9, 15, -7, 7, -15, 13, 15, -7, 7, -9, 0, 0], [-17, 10, 6, -5, -6, -17, 0, -5, -11, 0, -11, -5], [3, -16, -3, -11, 16, -11, -3, -3, 0, -5, -8, -5], [5, 4, 4, 5, 0, -5, 15, 0, -4, 9, -15, 5], [-10, 18, 2, -7, -2, -10, 0, 10, -4, 0, -4, 10], [-5, 1, 11, -16, -1, -16, 11, 5, 0, 20, -2, 20], [1, -1, 2, 10, -2, 1, 0, -2, 9, 0, 9, -2], [0, -7, 4, 14, 3, 2, -3, -2, 7, -14, -4, 9], [0, -15, -16, 3, 14, -8, -14, 8, 15, -3, 16, -19], [4, -3, -3, 4, 0, 4, 11, 0, -17, -31, -11, -4], [-2, -2, 2, 8, 2, 8, 2, 2, 0, -14, 13, -14], [-21, 8, 0, 0, -8, -18, 3, -3, -8, 18, -8, 21], [-16, -12, 2, -24, 12, -24, 2, 16, 0, 14, 3, 14], [13, -16, 0, 0, 8, 4, -1, -1, 8, -4, 16, -13], [-1, -4, 0, 0, 6, -14, 17, 7, 6, 14, 4, 1], [13, -6, -6, 26, 6, 13, 0, -9, 5, 0, 5, -9], [14, -1, -1, 23, -2, 23, -1, -23, 1, -14, 0, 0], [9, -5, -5, 9, 0, 20, -7, 0, -3, -8, 7, -20], [11, -9, -9, 11, 0, 14, -19, 0, 15, -7, 19, -14], [5, 6, -4, 28, 13, 11, 6, -28, 4, -5, 0, 0], [15, -9, 0, 0, -2, 3, -9, 0, -2, -3, 9, -15], [-13, -13, -13, -13, 0, 4, -7, 0, -7, -7, 7, -4], [10, 3, -22, 24, -3, 24, -22, -10, 0, -11, 10, -11], [2, 3, 0, 0, -15, 11, -2, -3, -15, -11, -3, -2], [-28, -7, -5, -17, 6, -27, -7, 17, 5, 28, 0, 0], [0, -6, -8, 20, 17, -5, -17, 5, 6, -20, 8, -3], [0, -1, 5, 13, 0, 15, 0, -15, 1, -13, -5, -17], [0, -15, 7, -11, -10, 3, 10, -3, 15, 11, -7, -1], [-11, 11, 0, 0, -16, 15, -6, -1, -16, -15, -11, 11], [16, 2, 10, 8, -10, 16, 0, -1, 4, 0, 4, -1], [12, 4, 9, 14, -9, 12, 0, 2, -7, 0, -7, 2], [0, 12, 0, 0, -20, 16, 17, -9, -20, -16, -12, 0], [0, -23, -26, 4, 16, 4, -16, -4, 23, -4, 26, -21], [6, 0, -6, 0, -2, 0, -13, 1, 13, 1, -2, 0], [1, -11, -4, -5, 11, -5, -4, -1, 0, -26, 19, -26], [1, -5, 0, 9, 7, 4, -5, -9, 0, -1, 0, 0], [-23, -2, 0, 0, -4, -7, 2, 6, -4, 7, 2, 23], [4, 0, -5, -12, -1, 0, -6, -3, 6, -3, -1, 12], [-4, 13, 13, -4, 0, -23, 25, 0, -11, -5, -25, 23], [-16, 0, -9, 7, 6, 0, -9, -11, 9, -11, 6, -7], [13, 7, 9, -5, -6, 4, 7, 5, -9, -13, 0, 0], [22, 8, 7, 6, -4, 27, 8, -6, -7, -22, 0, 0], [0, -4, -11, 0, 0, 3, 0, -3, 4, 0, 11, -7], [0, 16, 18, -22, -7, -14, 7, 14, -16, 22, -18, 21], [0, 4, 15, -10, -9, 19, 4, 10, -15, 0, 0, 0], [10, 4, 10, -10, 0, 14, 4, 10, -10, -10, 0, 0], [-3, 0, -15, 3, 9, 0, -23, 11, 23, 11, 9, -3], [18, -14, 4, -2, 14, -2, 4, -18, 0, -19, -3, -19], [13, 0, 11, -7, 0, 0, -9, 14, 9, 14, 0, 7], [-6, -4, -8, -25, 4, -25, -8, 6, 0, 7, 3, 7], [-21, 0, -22, -9, 0, 0, 2, -2, -2, -2, 0, 9], [4, -5, -11, 5, 5, 5, -11, -4, 0, -2, -10, -2], [5, -10, -14, 6, 15, -3, -10, -6, 14, -5, 0, 0], [1, -15, -6, 17, 6, 1, 0, -5, 6, 0, 6, -5], [1, -6, -10, 7, 10, 1, 0, -16, 27, 0, 27, -16], [14, 13, 18, 6, -18, 14, 0, -6, 8, 0, 8, -6], [20, -6, 0, 0, 7, 2, 12, -22, 7, -2, 6, -20], [-12, -10, -19, 13, 10, 13, -19, 12, 0, -8, 2, -8], [0, 13, 22, 1, -5, 5, 5, -5, -13, -1, -22, -2], [-10, -21, -21, -10, 0, 2, -20, 0, 22, 12, 20, -2], [-15, -4, -8, -3, 11, -18, -4, 3, 8, 15, 0, 0]];
    aps := ConvertToHeckeField(raw_aps);
    chi := MakeCharacter_290_k_Hecke( : Kf := Universe(aps));
    return ExtendMultiplicatively(weight, aps, chi);
end function;


// To make the newform (type ModFrm), type "MakeNewformModFrm_290_2_k_b();".
// 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_290_2_k_b(:prec:=12)
    chi := MakeCharacter_290_k();
    f_vec := qexpCoeffs();
    Kf := Universe(f_vec);
    // SetVerbose("ModularForms", true);
    // SetVerbose("ModularSymbols", true);
    S := CuspidalSubspace(ModularForms(chi, 2));
    S := BaseChange(S, Kf);
    maxprec := NextPrime(997) - 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_290_2_k_b();".
// 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_290_2_k_b( : sign := -1)
    R<x> := PolynomialRing(Rationals());
    chi := MakeCharacter_290_k();
    // SetVerbose("ModularSymbols", true);
    Snew := NewSubspace(CuspidalSubspace(ModularSymbols(chi,2,sign)));
    Vf := Kernel([<3,R![841, 464, 492, 273, 360, 237, 132, 12, -9, -7, 4, 1, 1]>],Snew);
    return Vf;
end function;