/* This code can be loaded, or copied and pasted, into Magma. It will load the data associated to the HMF, including the field, level, and Hecke and Atkin-Lehner eigenvalue data. At the *bottom* of the file, there is code to recreate the Hilbert modular form in Magma, by creating the HMF space and cutting out the corresponding Hecke irreducible subspace. From there, you can ask for more eigenvalues or modify as desired. It is commented out, as this computation may be lengthy. */ P := PolynomialRing(Rationals()); g := P![-1, -3, 4, 6, -4, -2, 1]; F := NumberField(g); ZF := Integers(F); NN := ideal; primesArray := [ [7, 7, w^2 - w - 2], [13, 13, w^4 - 2*w^3 - 3*w^2 + 5*w], [17, 17, -w^3 + w^2 + 3*w], [19, 19, w^3 - w^2 - 3*w + 1], [19, 19, -w^4 + w^3 + 4*w^2 - 2*w - 2], [23, 23, -w^4 + 2*w^3 + 3*w^2 - 3*w - 2], [31, 31, w^5 - 2*w^4 - 4*w^3 + 5*w^2 + 5*w - 1], [37, 37, -w^5 + 3*w^4 + 2*w^3 - 8*w^2 - w + 3], [37, 37, -w^5 + 2*w^4 + 4*w^3 - 6*w^2 - 4*w + 1], [47, 47, -w^3 + 2*w^2 + w - 3], [64, 2, -2], [67, 67, 2*w - 1], [79, 79, w^4 - w^3 - 4*w^2 + 2*w], [79, 79, -w^5 + 2*w^4 + 3*w^3 - 5*w^2 - w + 4], [97, 97, w^5 - 2*w^4 - 3*w^3 + 6*w^2 - 3], [97, 97, w^5 - 3*w^4 - 2*w^3 + 9*w^2 - 2*w - 4], [101, 101, w^5 - 2*w^4 - 3*w^3 + 5*w^2 - w - 2], [101, 101, w^5 - 3*w^4 - 2*w^3 + 10*w^2 - w - 5], [103, 103, 2*w^5 - 3*w^4 - 9*w^3 + 8*w^2 + 8*w - 3], [107, 107, w^2 - 2*w - 3], [109, 109, 2*w^5 - 3*w^4 - 9*w^3 + 7*w^2 + 9*w - 2], [113, 113, w^4 - w^3 - 5*w^2 + 3*w + 3], [121, 11, -2*w^5 + 4*w^4 + 7*w^3 - 10*w^2 - 5*w + 5], [125, 5, -w^5 + w^4 + 6*w^3 - 3*w^2 - 8*w], [125, 5, -w^3 + 2*w^2 + 3*w - 2], [127, 127, -2*w^5 + 4*w^4 + 6*w^3 - 9*w^2 - 2*w + 2], [131, 131, -w^5 + 2*w^4 + 3*w^3 - 4*w^2 - 2], [137, 137, w^4 - 2*w^3 - 3*w^2 + 5*w + 3], [139, 139, -w^5 + 3*w^4 + 2*w^3 - 8*w^2 + w], [157, 157, -2*w^5 + 4*w^4 + 7*w^3 - 10*w^2 - 6*w + 2], [157, 157, -2*w^5 + 4*w^4 + 7*w^3 - 11*w^2 - 6*w + 6], [173, 173, -w^5 + 2*w^4 + 5*w^3 - 7*w^2 - 5*w + 3], [179, 179, -w^4 + w^3 + 6*w^2 - 4*w - 4], [181, 181, w^4 - w^3 - 4*w^2 - w + 2], [181, 181, -w^5 + 3*w^4 + 2*w^3 - 8*w^2 + 2*w], [181, 181, w^5 - 3*w^4 - 3*w^3 + 9*w^2 + 3*w - 3], [191, 191, w^4 - w^3 - 4*w^2 + w + 4], [191, 191, w^5 - 2*w^4 - 5*w^3 + 8*w^2 + 4*w - 3], [193, 193, -w^5 + w^4 + 5*w^3 - 2*w^2 - 6*w + 1], [211, 211, -3*w^5 + 6*w^4 + 11*w^3 - 16*w^2 - 9*w + 7], [223, 223, 2*w^5 - 6*w^4 - 3*w^3 + 17*w^2 - 4*w - 6], [227, 227, w^5 - 3*w^4 - w^3 + 8*w^2 - 3*w - 4], [229, 229, -w^5 + 3*w^4 + w^3 - 7*w^2 + 5*w], [233, 233, -w^5 + 2*w^4 + 2*w^3 - 3*w^2 - 1], [251, 251, w^5 - 7*w^3 - 2*w^2 + 10*w + 1], [257, 257, 3*w^5 - 5*w^4 - 12*w^3 + 11*w^2 + 9*w - 1], [257, 257, -3*w^5 + 6*w^4 + 10*w^3 - 15*w^2 - 4*w + 3], [257, 257, -w^5 + 3*w^4 + 3*w^3 - 12*w^2 - w + 7], [263, 263, -2*w^5 + 6*w^4 + 4*w^3 - 17*w^2 + w + 5], [263, 263, -w^5 + 2*w^4 + 5*w^3 - 6*w^2 - 7*w + 2], [277, 277, -w^5 + 7*w^3 + 2*w^2 - 8*w - 5], [277, 277, w^5 - w^4 - 6*w^3 + 3*w^2 + 7*w - 2], [277, 277, -2*w^5 + 3*w^4 + 10*w^3 - 8*w^2 - 11*w + 2], [281, 281, -2*w^5 + 4*w^4 + 7*w^3 - 9*w^2 - 5*w + 1], [283, 283, -2*w^4 + 3*w^3 + 7*w^2 - 7*w - 2], [283, 283, -3*w^5 + 5*w^4 + 11*w^3 - 10*w^2 - 7*w], [293, 293, -w^5 + 2*w^4 + 4*w^3 - 7*w^2 - 4*w + 2], [311, 311, -2*w^5 + 5*w^4 + 6*w^3 - 14*w^2 - 3*w + 3], [311, 311, w^5 - 4*w^4 + 13*w^2 - 6*w - 6], [311, 311, -3*w^5 + 6*w^4 + 11*w^3 - 15*w^2 - 10*w + 3], [311, 311, -w^4 + w^3 + 4*w^2 - 2*w - 5], [317, 317, -2*w^5 + 4*w^4 + 6*w^3 - 8*w^2 - 3*w + 2], [317, 317, -w^5 + 8*w^3 - 11*w - 1], [331, 331, -w^4 + 6*w^2 + w - 5], [347, 347, -2*w^4 + 4*w^3 + 5*w^2 - 6*w], [349, 349, 2*w^5 - 5*w^4 - 4*w^3 + 11*w^2 - 3*w], [349, 349, -2*w^4 + 4*w^3 + 5*w^2 - 8*w + 1], [349, 349, -2*w^5 + 4*w^4 + 7*w^3 - 9*w^2 - 4*w + 1], [353, 353, 2*w^5 - 4*w^4 - 8*w^3 + 13*w^2 + 7*w - 6], [353, 353, -w^5 + 2*w^4 + 2*w^3 - 2*w^2 + w - 4], [353, 353, -w^5 + w^4 + 4*w^3 - 3*w - 4], [359, 359, -2*w^5 + 5*w^4 + 7*w^3 - 16*w^2 - 6*w + 6], [359, 359, w^5 - 2*w^4 - 4*w^3 + 6*w^2 + w - 3], [367, 367, -w^5 + 2*w^4 + 2*w^3 - 2*w^2 + 2*w - 2], [367, 367, -w^5 + 3*w^4 + 2*w^3 - 9*w^2 - w + 2], [373, 373, w^5 - 2*w^4 - 3*w^3 + 6*w^2 - w - 3], [379, 379, -w^5 + 4*w^4 + w^3 - 14*w^2 + w + 8], [379, 379, -2*w^5 + 5*w^4 + 6*w^3 - 14*w^2 - 5*w + 4], [383, 383, -w^5 + w^4 + 6*w^3 - 4*w^2 - 7*w + 1], [389, 389, 2*w^4 - 3*w^3 - 7*w^2 + 5*w + 4], [397, 397, -w^5 + 7*w^3 + 3*w^2 - 10*w - 4], [401, 401, -2*w^5 + 6*w^4 + 4*w^3 - 18*w^2 + w + 9], [401, 401, -3*w^5 + 7*w^4 + 8*w^3 - 18*w^2 - w + 7], [409, 409, -2*w^4 + 4*w^3 + 7*w^2 - 8*w - 6], [409, 409, 2*w^5 - 4*w^4 - 8*w^3 + 12*w^2 + 5*w - 5], [419, 419, -w^5 + 4*w^4 + w^3 - 14*w^2 + 3*w + 7], [419, 419, 2*w^5 - 6*w^4 - 4*w^3 + 19*w^2 - 2*w - 9], [439, 439, w^5 - 4*w^4 - w^3 + 12*w^2 - w - 4], [443, 443, w^5 - 2*w^4 - 4*w^3 + 7*w^2 + 4*w - 7], [457, 457, -3*w^5 + 5*w^4 + 12*w^3 - 11*w^2 - 10*w + 2], [457, 457, 2*w^5 - 3*w^4 - 9*w^3 + 9*w^2 + 7*w - 5], [457, 457, 3*w^5 - 6*w^4 - 10*w^3 + 15*w^2 + 7*w - 4], [463, 463, -w^5 + 4*w^4 + w^3 - 14*w^2 + 2*w + 6], [463, 463, -w^5 + 2*w^4 + 5*w^3 - 6*w^2 - 8*w + 1], [487, 487, w^5 - 2*w^4 - 4*w^3 + 4*w^2 + 5*w + 3], [499, 499, w^2 - w - 5], [499, 499, w^4 - w^3 - 5*w^2 + 4*w + 5], [523, 523, 2*w^5 - 2*w^4 - 11*w^3 + 4*w^2 + 12*w + 1], [557, 557, -2*w^5 + 3*w^4 + 9*w^3 - 8*w^2 - 9*w + 5], [563, 563, w^5 - 4*w^4 - w^3 + 12*w^2 - w - 3], [563, 563, -3*w^5 + 6*w^4 + 9*w^3 - 14*w^2 - 2*w + 3], [571, 571, -2*w^4 + 4*w^3 + 5*w^2 - 8*w - 1], [577, 577, 3*w^5 - 5*w^4 - 12*w^3 + 12*w^2 + 9*w - 1], [587, 587, 3*w^5 - 7*w^4 - 10*w^3 + 20*w^2 + 7*w - 7], [587, 587, w^5 - 3*w^4 - 3*w^3 + 9*w^2 + 2*w - 1], [587, 587, -3*w^5 + 6*w^4 + 11*w^3 - 16*w^2 - 8*w + 2], [593, 593, w^5 - 3*w^4 - 2*w^3 + 7*w^2 + 2*w + 1], [613, 613, -2*w^5 + 5*w^4 + 6*w^3 - 15*w^2 - w + 7], [631, 631, -w^5 + w^4 + 6*w^3 - 4*w^2 - 6*w + 5], [641, 641, -w^5 + 8*w^3 - w^2 - 10*w + 1], [641, 641, 2*w^5 - 4*w^4 - 8*w^3 + 10*w^2 + 9*w - 2], [643, 643, -2*w^4 + 4*w^3 + 7*w^2 - 8*w - 4], [643, 643, w^5 - w^4 - 5*w^3 + w^2 + 5*w + 5], [653, 653, w^5 - 3*w^4 - w^3 + 9*w^2 - 5*w - 4], [653, 653, w^5 - 3*w^4 - w^3 + 7*w^2 - w], [659, 659, w^5 - 3*w^4 - 3*w^3 + 10*w^2 + w - 3], [659, 659, w^4 - w^3 - 6*w^2 + 3*w + 4], [673, 673, -w^5 + 6*w^3 + 3*w^2 - 8*w - 4], [691, 691, 2*w^5 - 6*w^4 - 4*w^3 + 17*w^2 - w - 7], [691, 691, 3*w^5 - 6*w^4 - 11*w^3 + 17*w^2 + 8*w - 5], [701, 701, 2*w^5 - 3*w^4 - 9*w^3 + 9*w^2 + 6*w - 3], [701, 701, w^5 - 3*w^4 - 2*w^3 + 11*w^2 - 3*w - 8], [701, 701, -2*w^5 + 2*w^4 + 10*w^3 - 4*w^2 - 10*w + 1], [709, 709, 2*w^5 - 3*w^4 - 9*w^3 + 9*w^2 + 8*w - 4], [709, 709, w^2 - 5], [727, 727, 3*w^5 - 6*w^4 - 10*w^3 + 15*w^2 + 6*w - 4], [729, 3, -3], [733, 733, -w^5 + 4*w^4 - 11*w^2 + 3*w + 5], [733, 733, -2*w^5 + 2*w^4 + 9*w^3 - w^2 - 8*w - 4], [739, 739, 3*w^5 - 6*w^4 - 10*w^3 + 15*w^2 + 7*w - 3], [743, 743, w^5 - 4*w^4 - w^3 + 12*w^2 - 3], [751, 751, -w^5 + 2*w^4 + 5*w^3 - 8*w^2 - 6*w + 3], [757, 757, 3*w^5 - 5*w^4 - 12*w^3 + 12*w^2 + 8*w - 3], [761, 761, w^4 - 3*w^3 - 2*w^2 + 9*w - 1], [769, 769, 2*w^4 - 3*w^3 - 6*w^2 + 4*w + 4], [773, 773, 3*w^5 - 5*w^4 - 11*w^3 + 10*w^2 + 8*w - 2], [773, 773, -w^5 + w^4 + 5*w^3 - w^2 - 3*w - 2], [773, 773, 3*w^5 - 7*w^4 - 9*w^3 + 18*w^2 + 5*w - 5], [821, 821, 3*w^5 - 6*w^4 - 10*w^3 + 15*w^2 + 7*w - 5], [821, 821, 2*w^4 - 4*w^3 - 6*w^2 + 7*w + 1], [823, 823, -3*w^5 + 6*w^4 + 10*w^3 - 16*w^2 - 4*w + 5], [823, 823, -2*w^5 + 5*w^4 + 5*w^3 - 13*w^2 + w + 5], [827, 827, -3*w^5 + 5*w^4 + 13*w^3 - 13*w^2 - 11*w + 3], [827, 827, 2*w^5 - 5*w^4 - 6*w^3 + 16*w^2 + w - 5], [829, 829, 2*w^5 - 5*w^4 - 5*w^3 + 14*w^2 - 2*w - 5], [841, 29, w^5 - w^4 - 4*w^3 - w^2 + 4*w + 6], [853, 853, -2*w^5 + 5*w^4 + 5*w^3 - 13*w^2 - 2*w + 3], [857, 857, 2*w^5 - 2*w^4 - 10*w^3 + 4*w^2 + 9*w - 1], [857, 857, w^5 - 2*w^4 - 3*w^3 + 5*w^2 - 5], [857, 857, -3*w^5 + 5*w^4 + 13*w^3 - 14*w^2 - 10*w + 4], [863, 863, w^4 - 2*w^3 - 2*w^2 + 2*w - 2], [877, 877, w^5 - 3*w^4 - 2*w^3 + 11*w^2 - 3*w - 7], [881, 881, -w^5 + 4*w^4 - 12*w^2 + 3*w + 7], [883, 883, -4*w^5 + 8*w^4 + 13*w^3 - 19*w^2 - 6*w + 4], [883, 883, -2*w^5 + 6*w^4 + 3*w^3 - 16*w^2 + 4*w + 6], [883, 883, -w^5 + 4*w^4 - 13*w^2 + 5*w + 5], [961, 31, -2*w^5 + 4*w^4 + 8*w^3 - 11*w^2 - 6*w + 1], [967, 967, -w^5 + 7*w^3 - 7*w], [967, 967, w^5 - 4*w^4 - w^3 + 14*w^2 - 4*w - 5], [971, 971, -w^5 + 2*w^4 + 4*w^3 - 7*w^2 - 3*w + 1], [997, 997, 3*w^5 - 5*w^4 - 11*w^3 + 11*w^2 + 7*w - 1], [997, 997, 2*w^4 - 3*w^3 - 8*w^2 + 4*w + 5]]; primes := [ideal : I in primesArray]; heckePol := x^2 - 48; K := NumberField(heckePol); heckeEigenvaluesArray := [0, e, -e, -e, 4, -e, -e, -1, 0, 0, 13, 4, e, e, -2, e, 2*e, -2*e, 0, -12, 2, -18, 22, 18, 18, -8, -12, 0, -e, 0, 3*e, -3*e, -e, 10, 0, -22, -e, 0, -2*e, -20, e, 12, -22, e, 12, e, 4*e, 2*e, 0, -e, 26, -10, 10, 4*e, 3*e, -28, 4*e, 0, -2*e, 0, 0, 5*e, 30, -3*e, 36, 34, -2*e, -e, 18, 3*e, -e, 0, e, -16, -4*e, -26, -e, e, 24, 6, e, 18, -e, 2*e, 4*e, 12, 3*e, 8, 3*e, 0, e, 10, -3*e, 2*e, 4*e, 20, 0, -28, 4*e, -36, 36, -e, 2, -36, 36, -4*e, 3*e, -e, -16, -e, 3*e, -3*e, 4, 18, -18, -36, -4*e, -34, -44, -5*e, -30, 18, 5*e, 2*e, -2*e, -16, 22, -34, -7*e, -5*e, 24, -16, -5*e, -6, -50, -6, 6, -42, 6, 54, 32, -3*e, 5*e, -5*e, -5*e, -5*e, -e, 0, 6, 6*e, -24, 46, e, e, 7*e, -2*e, 50, 6*e, 40, 8*e, 26, -3*e]; heckeEigenvalues := AssociativeArray(); for i := 1 to #heckeEigenvaluesArray do heckeEigenvalues[primes[i]] := heckeEigenvaluesArray[i]; end for; ALEigenvalues := AssociativeArray(); ALEigenvalues[ideal] := 1; // EXAMPLE: // pp := Factorization(2*ZF)[1][1]; // heckeEigenvalues[pp]; print "To reconstruct the Hilbert newform f, type f, iso := Explode(make_newform());"; function make_newform(); M := HilbertCuspForms(F, NN); S := NewSubspace(M); // SetVerbose("ModFrmHil", 1); NFD := NewformDecomposition(S); newforms := [* Eigenform(U) : U in NFD *]; if #newforms eq 0 then; print "No Hilbert newforms at this level"; return 0; end if; print "Testing ", #newforms, " possible newforms"; newforms := [* f: f in newforms | IsIsomorphic(BaseField(f), K) *]; print #newforms, " newforms have the correct Hecke field"; if #newforms eq 0 then; print "No Hilbert newform found with the correct Hecke field"; return 0; end if; autos := Automorphisms(K); xnewforms := [* *]; for f in newforms do; if K eq RationalField() then; Append(~xnewforms, [* f, autos[1] *]); else; flag, iso := IsIsomorphic(K,BaseField(f)); for a in autos do; Append(~xnewforms, [* f, a*iso *]); end for; end if; end for; newforms := xnewforms; for P in primes do; xnewforms := [* *]; for f_iso in newforms do; f, iso := Explode(f_iso); if HeckeEigenvalue(f,P) eq iso(heckeEigenvalues[P]) then; Append(~xnewforms, f_iso); end if; end for; newforms := xnewforms; if #newforms eq 0 then; print "No Hilbert newform found which matches the Hecke eigenvalues"; return 0; else if #newforms eq 1 then; print "success: unique match"; return newforms[1]; end if; end if; end for; print #newforms, "Hilbert newforms found which match the Hecke eigenvalues"; return newforms[1]; end function;