/* 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, -8, 8, 6, -6, -1, 1]; F := NumberField(g); ZF := Integers(F); NN := ideal; primesArray := [ [7, 7, -w^5 + 5*w^3 - 5*w - 1], [27, 3, -2*w^5 + 10*w^3 - w^2 - 10*w + 2], [41, 41, -w^5 + 6*w^3 - w^2 - 7*w + 2], [41, 41, w^4 - w^3 - 4*w^2 + 3*w + 1], [41, 41, -2*w^5 + 12*w^3 - 2*w^2 - 17*w + 5], [41, 41, w^5 - 5*w^3 + 2*w^2 + 5*w - 5], [41, 41, -w^4 - 2*w^3 + 4*w^2 + 6*w - 3], [41, 41, -2*w^5 + 10*w^3 - w^2 - 10*w + 3], [43, 43, -w^5 + w^4 + 6*w^3 - 5*w^2 - 9*w + 4], [43, 43, -w^4 - w^3 + 4*w^2 + 4*w - 3], [43, 43, -w^4 + 3*w^2 + 1], [43, 43, -w^3 + w^2 + 4*w - 2], [43, 43, -w^5 + w^4 + 6*w^3 - 4*w^2 - 8*w + 3], [43, 43, -w^2 - w + 3], [64, 2, -2], [83, 83, -w^5 + 6*w^3 - w^2 - 10*w + 4], [83, 83, -2*w^5 + w^4 + 12*w^3 - 6*w^2 - 17*w + 6], [83, 83, w^5 - 6*w^3 + 2*w^2 + 8*w - 3], [83, 83, w^5 - 4*w^3 + w - 1], [83, 83, -2*w^5 + 11*w^3 - w^2 - 13*w + 1], [83, 83, w^5 - 5*w^3 + 2*w^2 + 6*w - 6], [125, 5, w^5 + w^4 - 5*w^3 - 4*w^2 + 6*w + 2], [125, 5, -w^5 - w^4 + 5*w^3 + 4*w^2 - 6*w - 1], [127, 127, w^5 - w^4 - 5*w^3 + 5*w^2 + 6*w - 4], [127, 127, -w^5 + 7*w^3 - 2*w^2 - 12*w + 5], [127, 127, -2*w^5 + w^4 + 11*w^3 - 5*w^2 - 13*w + 5], [127, 127, -2*w^3 + w^2 + 7*w - 2], [127, 127, -w^5 + 6*w^3 - 7*w], [127, 127, -w^4 - 2*w^3 + 4*w^2 + 7*w - 3], [167, 167, -w^5 - w^4 + 4*w^3 + 4*w^2 - 1], [167, 167, -2*w^4 + 7*w^2 + w - 3], [167, 167, w^5 - w^4 - 4*w^3 + 3*w^2 + w + 2], [167, 167, w^5 + w^4 - 4*w^3 - 4*w^2 + 3*w - 1], [167, 167, 2*w^5 - 11*w^3 + w^2 + 12*w - 3], [167, 167, 3*w^5 + w^4 - 16*w^3 - w^2 + 19*w - 6], [169, 13, w^5 - 4*w^3 + w^2 + 2*w - 3], [169, 13, -2*w^5 + 11*w^3 - 2*w^2 - 13*w + 4], [169, 13, -w^5 + 7*w^3 - w^2 - 11*w + 4], [211, 211, 3*w^5 - w^4 - 17*w^3 + 7*w^2 + 23*w - 9], [211, 211, -3*w^3 + 10*w - 1], [211, 211, w^5 + w^4 - 7*w^3 - 4*w^2 + 12*w - 1], [211, 211, 3*w^5 - w^4 - 16*w^3 + 6*w^2 + 18*w - 5], [211, 211, -2*w^5 + 12*w^3 - 3*w^2 - 16*w + 6], [211, 211, w^3 - 2*w^2 - 4*w + 3], [251, 251, 3*w^5 - 18*w^3 + 3*w^2 + 26*w - 8], [251, 251, 2*w^5 - 2*w^4 - 13*w^3 + 9*w^2 + 20*w - 7], [251, 251, w^5 + 2*w^4 - 5*w^3 - 8*w^2 + 6*w + 2], [251, 251, 2*w^5 + w^4 - 10*w^3 - 4*w^2 + 11*w], [251, 251, 2*w^4 - w^3 - 8*w^2 + 3*w + 3], [251, 251, w^4 + 3*w^3 - 5*w^2 - 9*w + 3], [293, 293, -2*w^5 - 2*w^4 + 10*w^3 + 7*w^2 - 11*w], [293, 293, -3*w^5 - w^4 + 16*w^3 + 2*w^2 - 18*w + 2], [293, 293, 2*w^5 - 13*w^3 + w^2 + 20*w - 5], [293, 293, w^5 - 2*w^4 - 7*w^3 + 8*w^2 + 12*w - 5], [293, 293, -2*w^4 - w^3 + 9*w^2 + 2*w - 7], [293, 293, -w^5 - w^4 + 4*w^3 + 5*w^2 - 3*w - 3], [337, 337, -w^5 + w^4 + 5*w^3 - 5*w^2 - 6*w + 3], [337, 337, -w^5 + 7*w^3 - 2*w^2 - 12*w + 4], [337, 337, -w^5 + 6*w^3 - 7*w - 1], [337, 337, 2*w^5 - w^4 - 11*w^3 + 5*w^2 + 13*w - 6], [337, 337, -w^4 - 2*w^3 + 4*w^2 + 7*w - 4], [337, 337, w^5 + w^4 - 5*w^3 - 2*w^2 + 5*w - 4], [379, 379, 2*w^5 - 2*w^4 - 11*w^3 + 8*w^2 + 13*w - 4], [379, 379, w^5 - 2*w^4 - 5*w^3 + 9*w^2 + 5*w - 4], [379, 379, 3*w^5 - 16*w^3 + w^2 + 18*w - 5], [379, 379, w^5 - 2*w^4 - 6*w^3 + 9*w^2 + 10*w - 7], [379, 379, -2*w^5 - 2*w^4 + 11*w^3 + 6*w^2 - 15*w + 1], [379, 379, w^5 - 7*w^3 + 3*w^2 + 13*w - 8], [419, 419, 2*w^5 - 10*w^3 + 3*w^2 + 11*w - 9], [419, 419, -3*w^5 + w^4 + 18*w^3 - 7*w^2 - 25*w + 8], [419, 419, -w^4 + 2*w^3 + 3*w^2 - 6*w + 3], [419, 419, -2*w^5 + 9*w^3 - w^2 - 6*w + 4], [419, 419, -w^5 + w^4 + 8*w^3 - 4*w^2 - 14*w + 5], [419, 419, 2*w^5 + w^4 - 11*w^3 - 2*w^2 + 12*w - 1], [421, 421, -w^3 - 2*w^2 + 4*w + 3], [421, 421, -3*w^5 + w^4 + 17*w^3 - 6*w^2 - 23*w + 9], [421, 421, 3*w^5 + w^4 - 17*w^3 - w^2 + 23*w - 7], [421, 421, 3*w^5 - 15*w^3 + w^2 + 16*w - 2], [421, 421, -2*w^4 - 3*w^3 + 9*w^2 + 9*w - 6], [421, 421, w^5 - w^4 - 6*w^3 + 5*w^2 + 6*w - 5], [461, 461, 2*w^5 - w^4 - 13*w^3 + 7*w^2 + 20*w - 8], [461, 461, -2*w^5 + w^4 + 10*w^3 - 5*w^2 - 9*w + 6], [461, 461, 2*w^4 + w^3 - 9*w^2 - 3*w + 4], [461, 461, w^5 - w^4 - 8*w^3 + 4*w^2 + 15*w - 5], [461, 461, 2*w^5 + w^4 - 10*w^3 - w^2 + 11*w - 7], [461, 461, w^5 - w^4 - 4*w^3 + 4*w^2 + 3*w], [463, 463, w^5 - 2*w^4 - 7*w^3 + 8*w^2 + 10*w - 6], [463, 463, w^5 - w^4 - 6*w^3 + 5*w^2 + 9*w - 8], [463, 463, w^5 - w^4 - 6*w^3 + 4*w^2 + 8*w + 1], [463, 463, -3*w^5 - w^4 + 15*w^3 + 3*w^2 - 15*w], [463, 463, -w^4 + 3*w^2 - 3], [463, 463, -w^4 - w^3 + 4*w^2 + 4*w + 1], [503, 503, w^5 - 7*w^3 + 12*w - 3], [503, 503, -3*w^5 - w^4 + 17*w^3 + w^2 - 23*w + 6], [503, 503, 2*w^5 - 10*w^3 + 3*w^2 + 10*w - 7], [503, 503, -w^5 + w^4 + 8*w^3 - 5*w^2 - 15*w + 8], [503, 503, -3*w^5 + 15*w^3 - w^2 - 16*w + 3], [503, 503, -2*w^5 + w^4 + 10*w^3 - 5*w^2 - 10*w + 7], [547, 547, 2*w^5 + w^4 - 11*w^3 - 4*w^2 + 14*w - 1], [547, 547, 3*w^5 - w^4 - 17*w^3 + 7*w^2 + 21*w - 9], [547, 547, -3*w^5 + w^4 + 17*w^3 - 5*w^2 - 21*w + 5], [547, 547, 2*w^4 + w^3 - 9*w^2 - 2*w + 4], [547, 547, 2*w^5 + w^4 - 10*w^3 - 3*w^2 + 12*w - 3], [547, 547, -w^5 - w^4 + 6*w^3 + 4*w^2 - 10*w - 3], [587, 587, 3*w^5 - w^4 - 16*w^3 + 7*w^2 + 19*w - 10], [587, 587, -2*w^5 - 2*w^4 + 9*w^3 + 7*w^2 - 7*w - 3], [587, 587, w^5 - 2*w^4 - 6*w^3 + 10*w^2 + 8*w - 7], [587, 587, 2*w^5 + w^4 - 12*w^3 - w^2 + 16*w - 5], [587, 587, -3*w^5 + 17*w^3 - w^2 - 22*w + 5], [587, 587, w^5 + w^4 - 7*w^3 - 3*w^2 + 13*w], [631, 631, -w^5 + 2*w^4 + 8*w^3 - 10*w^2 - 14*w + 9], [631, 631, 3*w^5 + w^4 - 16*w^3 - w^2 + 20*w - 6], [631, 631, -w^5 + 2*w^4 + 7*w^3 - 9*w^2 - 10*w + 6], [631, 631, 2*w^5 + 2*w^4 - 11*w^3 - 6*w^2 + 14*w - 1], [631, 631, -w^5 - w^4 + 6*w^3 + 5*w^2 - 8*w - 3], [631, 631, 3*w^5 - 16*w^3 + 2*w^2 + 20*w - 6], [673, 673, -w^5 - w^4 + 5*w^3 + w^2 - 5*w + 5], [673, 673, -w^4 + 6*w^2 - 6], [673, 673, 2*w^5 - 13*w^3 + 3*w^2 + 21*w - 8], [673, 673, w^5 - 2*w^4 - 5*w^3 + 9*w^2 + 6*w - 6], [673, 673, -3*w^5 + w^4 + 16*w^3 - 5*w^2 - 18*w + 5], [673, 673, -2*w^4 - 3*w^3 + 8*w^2 + 10*w - 5], [757, 757, 2*w^4 - w^3 - 8*w^2 + 3*w + 5], [757, 757, -3*w^5 + 18*w^3 - 3*w^2 - 26*w + 10], [757, 757, -w^5 + 6*w^3 - w^2 - 6*w + 4], [757, 757, -2*w^5 - w^4 + 10*w^3 + 4*w^2 - 11*w - 4], [757, 757, -3*w^5 + 15*w^3 - w^2 - 15*w + 1], [757, 757, w^5 + w^4 - 5*w^3 - 4*w^2 + 7*w + 4], [797, 797, w^5 - w^4 - 6*w^3 + 3*w^2 + 9*w - 3], [797, 797, -w^5 - w^4 + 7*w^3 + 4*w^2 - 11*w], [797, 797, 2*w^5 + w^4 - 10*w^3 - 4*w^2 + 10*w + 4], [797, 797, 3*w^5 + w^4 - 17*w^3 - w^2 + 22*w - 5], [797, 797, -2*w^5 + w^4 + 11*w^3 - 4*w^2 - 14*w], [797, 797, 2*w^5 - 12*w^3 + w^2 + 18*w - 6], [839, 839, w^5 + w^4 - 5*w^3 - w^2 + 4*w - 5], [839, 839, -4*w^5 + w^4 + 22*w^3 - 6*w^2 - 27*w + 8], [839, 839, 2*w^5 + w^4 - 13*w^3 - w^2 + 21*w - 6], [839, 839, w^5 - w^4 - 7*w^3 + 4*w^2 + 9*w - 2], [839, 839, w^5 + 2*w^4 - 2*w^3 - 8*w^2 - 5*w + 5], [839, 839, -w^5 + 2*w^4 + 5*w^3 - 10*w^2 - 6*w + 8], [841, 29, 2*w^5 - 13*w^3 + 2*w^2 + 19*w - 6], [841, 29, -3*w^5 + 17*w^3 - 3*w^2 - 21*w + 7], [841, 29, 3*w^5 - 16*w^3 + 3*w^2 + 18*w - 7], [881, 881, 3*w^5 + w^4 - 17*w^3 - w^2 + 22*w - 7], [881, 881, 2*w^5 - w^4 - 12*w^3 + 6*w^2 + 15*w - 8], [881, 881, -w^5 + 7*w^3 - 2*w^2 - 11*w + 8], [881, 881, -2*w^5 - w^4 + 10*w^3 + 2*w^2 - 10*w], [881, 881, 2*w^5 - w^4 - 11*w^3 + 6*w^2 + 13*w - 4], [881, 881, 2*w^5 - 12*w^3 + w^2 + 16*w - 6], [883, 883, 2*w^5 + w^4 - 13*w^3 - 2*w^2 + 19*w - 4], [883, 883, -2*w^5 + w^4 + 14*w^3 - 6*w^2 - 22*w + 8], [883, 883, w^5 + w^4 - 3*w^3 - 5*w^2 + 5], [883, 883, -4*w^5 + 22*w^3 - 4*w^2 - 27*w + 10], [883, 883, -4*w^5 + w^4 + 23*w^3 - 8*w^2 - 30*w + 12], [883, 883, 3*w^5 + 2*w^4 - 16*w^3 - 6*w^2 + 19*w - 1], [967, 967, -w^5 + 2*w^4 + 7*w^3 - 9*w^2 - 13*w + 5], [967, 967, -3*w^5 + 16*w^3 - 3*w^2 - 20*w + 9], [967, 967, 2*w^5 - 13*w^3 + 2*w^2 + 18*w - 6], [967, 967, 2*w^5 - 2*w^4 - 12*w^3 + 9*w^2 + 15*w - 8], [967, 967, 3*w^5 - 16*w^3 + 4*w^2 + 18*w - 9], [967, 967, 2*w^5 + 2*w^4 - 11*w^3 - 6*w^2 + 13*w]]; primes := [ideal : I in primesArray]; heckePol := x; K := Rationals(); e := 1; heckeEigenvaluesArray := [-2, -9, -3, -6, -6, -3, 1, 6, 7, -8, 1, 1, -8, 10, -11, -12, -9, -15, -9, 0, -6, 18, -3, -10, 8, 11, 2, -16, 5, -6, 21, 15, -12, 0, 3, 20, 5, -19, -5, 7, 16, -14, 10, -23, 21, 12, -15, -21, 18, 0, 0, 18, 30, -21, 12, 9, -11, 13, 19, -8, -23, -32, 4, 13, -26, -2, -20, -29, -33, -39, -24, -30, 36, 36, -19, 26, -10, -19, 38, -25, -30, 18, 24, -27, 12, -6, -1, -19, 8, 17, -19, 20, -30, 36, -6, -30, -9, -27, -22, 20, -4, -7, 26, 35, -15, 24, 24, -18, 18, -42, -1, -16, -25, -37, 29, 14, 46, -26, 28, 1, -44, 1, -29, 16, 7, -38, -14, -20, 6, -12, -54, -54, 0, -27, 36, -51, -24, 21, 3, 30, -14, -23, -5, 18, 42, -15, 15, 30, -54, 52, 34, 4, -44, -8, 46, -4, -10, 32, 14, -4, 47]; 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;