// Make newform 5070.2.b.s in Magma, downloaded from the LMFDB on 28 March 2024. // To make the character of type GrpDrchElt, type "MakeCharacter_5070_b();" // To make the character of type GrpDrchElt with Codomain the HeckeField, type "MakeCharacter_5070_b_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_5070_2_b_s();". // 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_5070_2_b_s();". // 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, 0, 6, 0, 5, 0, 1]; Kf := NumberField(Polynomial([elt : elt in poly])); AssignNames(~Kf, ["nu"]); end if; Rf_num := [[1, 0, 0, 0, 0, 0], [0, 1, 0, 0, 0, 0], [2, 0, 1, 0, 0, 0], [0, 3, 0, 1, 0, 0], [1, 0, 3, 0, 1, 0], [0, 3, 0, 4, 0, 1]]; Rf_basisdens := [1, 1, 1, 1, 1, 1]; 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_5070_b();" function MakeCharacter_5070_b() N := 5070; order := 2; char_gens := [1691, 4057, 1861]; v := [2, 2, 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; // To make the character of type GrpDrchElt with Codomain the HeckeField, type "MakeCharacter_5070_b_Hecke();" function MakeCharacter_5070_b_Hecke(Kf) N := 5070; order := 2; char_gens := [1691, 4057, 1861]; char_values := [[1, 0, 0, 0, 0, 0], [1, 0, 0, 0, 0, 0], [-1, 0, 0, 0, 0, 0]]; assert UnitGenerators(DirichletGroup(N)) eq char_gens; values := ConvertToHeckeField(char_values : pass_field := true, 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 := 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 := PowerSeriesRing(FXY : Precision := log_prec + 1); recursion := Coefficients(1/(1 - X*T + Y*T^2)); coeffs := [F!0: i in [1..(prec+1)]]; 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, 1], [-1, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 1], [0, 1, 0, 1, 0, 0], [0, -1, 0, 0, 0, 5], [0, 0, 0, 0, 0, 0], [-1, 0, -1, 0, 1, 0], [0, 5, 0, -3, 0, -5], [5, 0, -7, 0, -3, 0], [1, 0, 3, 0, 6, 0], [0, 3, 0, -4, 0, -7], [0, -1, 0, -3, 0, -2], [0, -5, 0, 5, 0, -1], [0, 0, 2, 0, 3, 0], [0, 4, 0, -2, 0, 5], [2, 0, -3, 0, 0, 0], [0, -3, 0, -4, 0, 2], [-4, 0, -6, 0, 1, 0], [0, 0, 0, -1, 0, -2], [0, 4, 0, -7, 0, -8], [0, 0, 0, 7, 0, -2], [-6, 0, 5, 0, 6, 0], [0, -5, 0, -2, 0, -3], [0, 2, 0, 5, 0, 2], [0, 3, 0, -3, 0, -2], [4, 0, -4, 0, 2, 0], [9, 0, 0, 0, 0, 0], [-8, 0, 2, 0, 3, 0], [0, -4, 0, 5, 0, 3], [2, 0, -8, 0, -17, 0], [-4, 0, 1, 0, 12, 0], [-6, 0, 0, 0, 5, 0], [0, 7, 0, -15, 0, 1], [9, 0, -10, 0, -12, 0], [0, 9, 0, 1, 0, -5], [0, 11, 0, -8, 0, -6], [10, 0, -3, 0, 1, 0], [0, 9, 0, -4, 0, -20], [0, -5, 0, 14, 0, 7], [-14, 0, 12, 0, 9, 0], [-13, 0, 14, 0, 8, 0], [1, 0, 1, 0, -2, 0], [-8, 0, 13, 0, 20, 0], [0, 4, 0, 3, 0, -5], [0, 2, 0, 5, 0, -12], [9, 0, 7, 0, -7, 0], [-6, 0, 10, 0, 14, 0], [0, -6, 0, 13, 0, -5], [0, 2, 0, 2, 0, -13], [0, -3, 0, 3, 0, 11], [1, 0, 2, 0, -10, 0], [0, 7, 0, 10, 0, -1], [0, 12, 0, -3, 0, -5], [-13, 0, 3, 0, 13, 0], [2, 0, 11, 0, 1, 0], [9, 0, -1, 0, 2, 0], [0, 0, 10, 0, -3, 0], [0, 22, 0, -17, 0, -16], [-2, 0, 11, 0, -4, 0], [0, 12, 0, -1, 0, 6], [1, 0, -9, 0, 7, 0], [0, -18, 0, 0, 0, 4], [0, -10, 0, 7, 0, 11], [-16, 0, -4, 0, -5, 0], [11, 0, -14, 0, -11, 0], [0, -3, 0, -4, 0, -14], [0, 21, 0, -15, 0, -13], [1, 0, 0, 0, 6, 0], [2, 0, -9, 0, -17, 0], [0, 5, 0, -6, 0, 7], [0, -7, 0, 13, 0, -7], [0, 23, 0, -17, 0, -15], [-5, 0, 18, 0, 1, 0], [0, 0, -10, 0, -16, 0], [0, -9, 0, -3, 0, -8], [0, -15, 0, 2, 0, 16], [-6, 0, 6, 0, 3, 0], [0, -17, 0, 2, 0, 11], [0, -9, 0, -2, 0, -3], [0, 0, 0, 0, 0, -9], [9, 0, 13, 0, -4, 0], [0, 13, 0, 1, 0, -3], [0, 21, 0, -12, 0, -22], [-4, 0, 0, 0, -15, 0], [10, 0, -15, 0, -20, 0], [1, 0, -15, 0, -21, 0], [0, 0, 0, 1, 0, 5], [0, 8, 0, -17, 0, -12], [0, -11, 0, 21, 0, 13], [0, -5, 0, -16, 0, -2], [-8, 0, 3, 0, 7, 0], [0, 26, 0, -4, 0, -17], [0, 0, 0, 5, 0, 24], [0, 0, 20, 0, -10, 0], [0, -4, 0, 2, 0, -28], [-18, 0, 23, 0, 14, 0], [0, 13, 0, -16, 0, -30], [17, 0, 0, 0, 7, 0], [-6, 0, 0, 0, 28, 0], [0, 5, 0, -5, 0, -30], [-5, 0, 5, 0, 24, 0], [0, 5, 0, -5, 0, -3], [19, 0, 4, 0, 9, 0], [-36, 0, 11, 0, 3, 0], [-32, 0, 15, 0, 9, 0], [0, -16, 0, 12, 0, 20], [0, 4, 0, 3, 0, -7], [0, -16, 0, 8, 0, 14], [-6, 0, -11, 0, 3, 0], [26, 0, -17, 0, -12, 0], [28, 0, -32, 0, -13, 0], [0, -13, 0, 12, 0, 7], [0, -1, 0, -1, 0, -16], [0, -10, 0, 13, 0, -13], [0, 10, 0, -5, 0, -32], [-22, 0, 6, 0, -2, 0], [0, -1, 0, -19, 0, -17], [2, 0, -13, 0, -4, 0], [-30, 0, 18, 0, 12, 0], [-26, 0, 13, 0, 5, 0], [0, -13, 0, 0, 0, -14], [5, 0, 2, 0, 18, 0], [5, 0, -8, 0, 8, 0], [0, -13, 0, 8, 0, -2], [0, -11, 0, -1, 0, 18], [-16, 0, -4, 0, 1, 0], [0, 34, 0, -11, 0, -20], [16, 0, 6, 0, 21, 0], [-23, 0, -1, 0, 13, 0], [0, 7, 0, -9, 0, 17], [0, -30, 0, 13, 0, 28], [0, -21, 0, 8, 0, 18], [-7, 0, -8, 0, 20, 0], [16, 0, -13, 0, 6, 0], [0, -5, 0, 0, 0, 24], [0, 15, 0, 7, 0, -4], [0, -13, 0, 34, 0, 13], [0, 7, 0, -27, 0, 4], [13, 0, -9, 0, -14, 0], [37, 0, -32, 0, -15, 0], [0, -2, 0, -8, 0, 8], [0, 19, 0, -6, 0, 16], [-25, 0, 22, 0, 17, 0], [0, 17, 0, -24, 0, -14], [-27, 0, 27, 0, 11, 0], [0, -22, 0, -8, 0, -7], [0, 1, 0, 16, 0, 30], [-28, 0, 2, 0, -7, 0], [-14, 0, 11, 0, -8, 0], [0, 20, 0, -11, 0, 7], [0, -32, 0, 9, 0, 23], [-33, 0, 33, 0, 27, 0], [3, 0, 13, 0, 25, 0], [-12, 0, 14, 0, 12, 0], [-13, 0, -20, 0, -25, 0], [-11, 0, -12, 0, -10, 0], [-33, 0, -9, 0, -3, 0], [0, -19, 0, 7, 0, -13], [20, 0, -27, 0, -15, 0], [0, -20, 0, 24, 0, 21], [0, -11, 0, -3, 0, 4], [32, 0, 5, 0, 2, 0], [0, 7, 0, -10, 0, -39], [-17, 0, -7, 0, 24, 0], [0, 11, 0, -19, 0, -36], [0, -2, 0, 1, 0, -25], [38, 0, -7, 0, -5, 0], [1, 0, -5, 0, -8, 0], [0, -4, 0, -3, 0, -42], [2, 0, 14, 0, -13, 0], [0, -15, 0, -7, 0, 19], [0, -15, 0, 8, 0, 6], [17, 0, -31, 0, -10, 0], [0, 0, 0, -11, 0, 10], [19, 0, 1, 0, -24, 0], [11, 0, 11, 0, 11, 0], [0, -36, 0, 19, 0, 16], [0, 22, 0, 11, 0, 10], [-3, 0, -25, 0, -27, 0], [26, 0, -44, 0, -24, 0], [0, -12, 0, -7, 0, -28], [3, 0, -18, 0, -17, 0], [-8, 0, -26, 0, -11, 0], [0, 3, 0, -4, 0, -47], [0, 52, 0, -29, 0, -49], [29, 0, -16, 0, 4, 0], [6, 0, -24, 0, -8, 0], [0, -19, 0, 9, 0, 59], [0, -5, 0, -18, 0, 1], [0, -20, 0, -21, 0, 3], [-3, 0, 37, 0, -3, 0], [0, 21, 0, -1, 0, 5], [-4, 0, 11, 0, 18, 0], [0, -14, 0, 22, 0, 13], [-8, 0, -10, 0, 8, 0], [-11, 0, -21, 0, -34, 0], [0, -8, 0, -28, 0, -6], [-13, 0, 39, 0, 19, 0], [0, 20, 0, -11, 0, -10], [-19, 0, -2, 0, -19, 0], [0, -27, 0, 14, 0, 26], [-11, 0, 0, 0, 34, 0], [0, -2, 0, 24, 0, -9], [-6, 0, 36, 0, 6, 0], [0, 18, 0, -25, 0, -1], [23, 0, -6, 0, -2, 0], [0, 11, 0, 20, 0, 22], [-14, 0, 23, 0, 0, 0], [0, 8, 0, -16, 0, 28], [-20, 0, 13, 0, 18, 0], [24, 0, -42, 0, -26, 0], [-21, 0, 26, 0, -7, 0], [-30, 0, 16, 0, 19, 0], [0, 19, 0, -1, 0, 9], [0, 2, 0, -6, 0, -8], [0, 15, 0, -44, 0, -8], [8, 0, 2, 0, -13, 0], [-19, 0, 14, 0, 20, 0], [0, -17, 0, -32, 0, -13], [0, -18, 0, 3, 0, 1], [-1, 0, -18, 0, -28, 0], [0, -20, 0, 18, 0, 55], [0, 17, 0, -30, 0, -16], [0, 1, 0, -15, 0, -30], [1, 0, 10, 0, 15, 0], [3, 0, 29, 0, 7, 0], [3, 0, -24, 0, -3, 0], [27, 0, -34, 0, 3, 0], [-19, 0, -9, 0, 17, 0], [0, 10, 0, -25, 0, -38], [12, 0, -19, 0, 15, 0], [-3, 0, -24, 0, -7, 0], [0, 18, 0, 7, 0, -23], [-35, 0, 1, 0, 20, 0], [-11, 0, -26, 0, -2, 0], [0, -7, 0, 10, 0, -48], [0, 7, 0, -31, 0, 1], [0, -18, 0, 13, 0, -13], [16, 0, -1, 0, -7, 0], [4, 0, -11, 0, -17, 0], [0, 50, 0, -21, 0, -30], [22, 0, -17, 0, -31, 0], [5, 0, 18, 0, -2, 0], [0, 6, 0, -16, 0, 13], [0, -24, 0, 6, 0, -8], [2, 0, -23, 0, -11, 0], [0, -9, 0, 18, 0, 34], [0, -34, 0, 18, 0, 31], [0, 21, 0, 6, 0, -10], [12, 0, 29, 0, -4, 0], [0, -9, 0, 27, 0, 21], [0, 1, 0, -5, 0, -31], [0, -43, 0, 35, 0, 18], [16, 0, 11, 0, 33, 0], [-11, 0, 3, 0, -10, 0], [0, 9, 0, -14, 0, 22], [42, 0, 2, 0, -22, 0], [0, 21, 0, -6, 0, -1], [8, 0, -5, 0, -15, 0], [0, 0, 0, 19, 0, -39], [15, 0, -20, 0, -17, 0], [-43, 0, -6, 0, 11, 0], [0, -11, 0, -21, 0, -28], [8, 0, -18, 0, -17, 0], [0, 24, 0, -28, 0, 6], [-19, 0, 22, 0, 6, 0], [0, -10, 0, 5, 0, 49], [0, -25, 0, 35, 0, 8], [0, 4, 0, 23, 0, 34], [7, 0, 1, 0, -27, 0], [11, 0, -20, 0, -38, 0], [0, -6, 0, 5, 0, 15], [0, -9, 0, 7, 0, -9], [32, 0, -8, 0, -5, 0], [17, 0, 27, 0, -15, 0], [0, -2, 0, -26, 0, -33], [0, -21, 0, -8, 0, -4], [0, 6, 0, 32, 0, -14], [0, 17, 0, -45, 0, -24], [30, 0, 11, 0, 16, 0], [3, 0, -8, 0, 4, 0], [0, 32, 0, -28, 0, -36], [-8, 0, 30, 0, 5, 0], [0, 37, 0, -7, 0, -27], [0, 25, 0, -10, 0, -35], [45, 0, -3, 0, 19, 0], [55, 0, 14, 0, -12, 0], [0, -10, 0, -2, 0, 11], [0, 16, 0, 2, 0, 15], [-46, 0, 9, 0, 12, 0], [-38, 0, 8, 0, -16, 0], [-45, 0, -9, 0, -8, 0], [0, -36, 0, 37, 0, 37], [0, 31, 0, 21, 0, 15], [-29, 0, -3, 0, -3, 0], [-30, 0, -3, 0, 43, 0], [10, 0, -20, 0, -24, 0], [34, 0, 7, 0, 11, 0], [-52, 0, 41, 0, 28, 0], [0, 26, 0, -36, 0, -49], [-66, 0, 23, 0, 6, 0], [0, -6, 0, 22, 0, 11], [14, 0, -10, 0, -30, 0], [5, 0, -33, 0, -41, 0], [6, 0, -12, 0, -16, 0], [0, 12, 0, 2, 0, 12], [28, 0, 4, 0, -5, 0], [18, 0, -12, 0, -9, 0], [0, -47, 0, -3, 0, 23], [15, 0, -40, 0, -28, 0], [-39, 0, 21, 0, 5, 0], [0, -30, 0, 31, 0, 42], [0, 0, 30, 0, -19, 0], [42, 0, 2, 0, -19, 0], [0, 26, 0, -21, 0, -36], [-45, 0, 40, 0, 39, 0], [0, 3, 0, -11, 0, -28], [0, 51, 0, -38, 0, -25], [0, 27, 0, -25, 0, -4], [29, 0, -36, 0, -17, 0], [7, 0, -3, 0, 8, 0], [0, 18, 0, -44, 0, 16], [18, 0, -17, 0, -24, 0], [0, 22, 0, 12, 0, 22], [0, -36, 0, 15, 0, -2], [-37, 0, 19, 0, 39, 0], [0, -23, 0, 40, 0, -26], [0, 18, 0, -29, 0, -10], [-27, 0, 20, 0, 24, 0], [-22, 0, 9, 0, -17, 0], [0, 25, 0, -25, 0, -1], [61, 0, 7, 0, -6, 0], [-60, 0, 43, 0, 18, 0], [0, 30, 0, 6, 0, 27], [0, -16, 0, -5, 0, 47], [0, 9, 0, -10, 0, -5], [0, -4, 0, -31, 0, -20], [0, -4, 0, -12, 0, 15], [0, 31, 0, -11, 0, -63], [-39, 0, 1, 0, 17, 0], [0, 12, 0, 13, 0, -25], [-1, 0, -24, 0, -10, 0], [0, -28, 0, 21, 0, -27], [13, 0, 5, 0, 10, 0], [0, -24, 0, 34, 0, 56], [-16, 0, 10, 0, -21, 0], [12, 0, -17, 0, 27, 0], [0, 0, 0, -4, 0, -12], [0, -13, 0, -32, 0, -27], [-61, 0, 32, 0, 11, 0], [0, 14, 0, 14, 0, -25], [0, -21, 0, 29, 0, 27], [0, 23, 0, 5, 0, 2], [-24, 0, 0, 0, -11, 0], [40, 0, 6, 0, 13, 0], [-2, 0, 12, 0, -4, 0], [0, 30, 0, -9, 0, -14], [0, 6, 0, -37, 0, 12], [-26, 0, 9, 0, -3, 0], [0, -20, 0, 61, 0, 12], [0, 3, 0, 7, 0, -37], [44, 0, 5, 0, 24, 0], [-57, 0, 47, 0, 26, 0], [0, -33, 0, 42, 0, 36], [-29, 0, 48, 0, 31, 0], [41, 0, 1, 0, 24, 0], [0, -26, 0, 8, 0, 51], [0, -47, 0, 39, 0, 31], [-26, 0, 26, 0, 12, 0], [28, 0, -17, 0, 8, 0], [-23, 0, -14, 0, 9, 0], [0, -1, 0, 43, 0, 13], [-35, 0, 58, 0, 22, 0], [-58, 0, 66, 0, 40, 0], [-8, 0, -4, 0, 6, 0], [0, 39, 0, -31, 0, -45], [-8, 0, 5, 0, -19, 0], [0, -13, 0, -25, 0, -41], [18, 0, 2, 0, -23, 0], [33, 0, 33, 0, -1, 0], [0, -2, 0, -34, 0, -7], [0, 13, 0, 37, 0, 8], [0, 0, 0, -22, 0, -16], [0, 20, 0, -11, 0, -47], [0, 45, 0, -1, 0, 4], [0, -2, 0, -44, 0, 15], [0, -42, 0, -5, 0, 25], [72, 0, -53, 0, -39, 0], [0, -12, 0, 10, 0, -5], [24, 0, -4, 0, -28, 0], [0, -47, 0, 14, 0, 42], [0, -9, 0, 19, 0, -28], [0, 20, 0, 22, 0, -23], [-45, 0, 60, 0, 20, 0], [0, -17, 0, -9, 0, 48], [26, 0, -23, 0, -32, 0], [0, -59, 0, 53, 0, 36], [28, 0, -35, 0, -15, 0], [-21, 0, 52, 0, -10, 0], [0, -23, 0, -33, 0, -30], [0, -30, 0, 52, 0, 15], [38, 0, -12, 0, 21, 0], [0, -29, 0, 31, 0, 59], [0, -41, 0, -5, 0, 22], [0, -41, 0, -20, 0, -31], [26, 0, -5, 0, -24, 0], [0, 44, 0, -14, 0, -30], [0, 0, 0, -1, 0, -18], [0, 1, 0, 9, 0, 35], [0, -36, 0, 6, 0, -6], [-44, 0, 55, 0, 22, 0], [0, 0, -21, 0, -17, 0], [64, 0, -29, 0, -30, 0], [-33, 0, -7, 0, 29, 0], [72, 0, -16, 0, 1, 0], [-16, 0, -12, 0, 1, 0], [0, 37, 0, -47, 0, -20], [8, 0, -15, 0, 10, 0], [0, 35, 0, -5, 0, -26], [61, 0, -37, 0, -19, 0], [-33, 0, 24, 0, 13, 0], [0, -13, 0, 25, 0, -29], [0, -9, 0, -14, 0, -3], [28, 0, -27, 0, 3, 0], [0, 57, 0, -17, 0, -44], [0, 24, 0, -7, 0, -54], [52, 0, 7, 0, -26, 0], [0, -58, 0, 52, 0, 65], [0, -28, 0, 52, 0, 5], [9, 0, -49, 0, -48, 0]]; aps := ConvertToHeckeField(raw_aps); chi := MakeCharacter_5070_b_Hecke(Universe(aps)); return ExtendMultiplicatively(weight, aps, chi); end function; // To make the newform (type ModFrm), type "MakeNewformModFrm_5070_2_b_s();". // 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_5070_2_b_s(:prec:=6) chi := MakeCharacter_5070_b(); 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_5070_2_b_s();". // 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_5070_2_b_s( : sign := -1) R := PolynomialRing(Rationals()); chi := MakeCharacter_5070_b(); // SetVerbose("ModularSymbols", true); Snew := NewSubspace(CuspidalSubspace(ModularSymbols(chi,2,sign))); Vf := Kernel([<7,R![49, 0, 49, 0, 14, 0, 1]>,<11,R![8281, 0, 1421, 0, 70, 0, 1]>,<17,R![-13, -4, 3, 1]>,<31,R![49, 0, 1421, 0, 126, 0, 1]>],Snew); return Vf; end function;