/* 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, -2, -5, 0, 1]; F := NumberField(g); ZF := Integers(F); NN := ideal; primesArray := [ [4, 2, -w^3 + 4*w + 1], [5, 5, w - 1], [7, 7, -w^2 + w + 2], [13, 13, -w^3 + w^2 + 4*w], [13, 13, -w^2 + 3], [17, 17, -w^2 + 2], [19, 19, -w^3 + 5*w], [31, 31, -w^2 + 2*w + 3], [37, 37, -2*w^3 + w^2 + 8*w - 1], [43, 43, -w - 3], [53, 53, -w^3 + 2*w^2 + 3*w - 2], [53, 53, w^3 - 6*w - 2], [59, 59, 2*w^3 - w^2 - 10*w - 2], [61, 61, 2*w^3 - w^2 - 10*w], [61, 61, 2*w^3 - w^2 - 8*w], [71, 71, 2*w^3 - 9*w - 2], [73, 73, -w^3 - w^2 + 6*w + 3], [81, 3, -3], [83, 83, -w^3 + 2*w^2 + 3*w - 3], [101, 101, 2*w^3 - 8*w - 3], [125, 5, w^3 + w^2 - 4*w - 6], [127, 127, 2*w^3 - w^2 - 7*w - 2], [127, 127, w^3 - 7*w - 7], [131, 131, w^3 - 3*w - 4], [131, 131, 3*w^3 - 13*w - 7], [137, 137, w^2 + w - 4], [137, 137, -w^3 + 2*w^2 + 4*w - 4], [149, 149, 3*w + 5], [157, 157, -2*w^3 - w^2 + 7*w + 2], [157, 157, -2*w^3 + 2*w^2 + 9*w - 1], [163, 163, -2*w^3 + w^2 + 7*w], [163, 163, -3*w^3 + w^2 + 15*w + 3], [163, 163, 2*w^3 - 7*w - 1], [163, 163, 2*w^3 - 11*w - 5], [167, 167, -2*w^3 + w^2 + 9*w - 4], [167, 167, w^3 - w^2 - 7*w + 1], [167, 167, w^3 - w^2 - 7*w - 1], [167, 167, w^2 - 2*w - 5], [169, 13, w^3 + w^2 - 6*w - 2], [173, 173, -3*w^3 + 13*w + 3], [181, 181, 2*w^2 + w - 4], [191, 191, 2*w^3 - 10*w - 1], [191, 191, -2*w^3 + 2*w^2 + 6*w - 3], [193, 193, 3*w^3 - 13*w - 6], [197, 197, -w^3 + w^2 + 2*w - 3], [197, 197, w^3 + w^2 - 7*w - 7], [199, 199, -w^2 + 2*w + 6], [223, 223, -2*w^3 + w^2 + 11*w + 2], [227, 227, -3*w^3 + 2*w^2 + 15*w - 1], [229, 229, -w^3 + w^2 + 6*w - 5], [233, 233, 2*w^3 - 11*w - 4], [239, 239, -2*w^3 + 11*w + 3], [251, 251, 2*w^3 - w^2 - 10*w - 4], [257, 257, -2*w^3 + w^2 + 6*w + 1], [257, 257, w^3 - 7*w - 2], [263, 263, 2*w^3 - 9*w], [269, 269, w^3 - 4*w - 6], [269, 269, -2*w^3 + 8*w - 3], [271, 271, 2*w^2 - w - 5], [277, 277, -3*w^3 + 2*w^2 + 11*w - 2], [277, 277, 3*w^3 - w^2 - 15*w - 5], [281, 281, 2*w^2 - 5], [283, 283, -3*w^3 + 2*w^2 + 12*w + 2], [283, 283, -2*w^3 + w^2 + 6*w + 6], [293, 293, -2*w^3 - w^2 + 12*w + 7], [293, 293, -2*w^3 + 9*w - 1], [311, 311, -3*w^3 + w^2 + 12*w + 4], [313, 313, -w^3 + w^2 + 2*w - 4], [313, 313, -4*w^3 + 2*w^2 + 16*w - 3], [331, 331, 3*w^3 - w^2 - 16*w - 5], [331, 331, 2*w^3 - 2*w^2 - 8*w - 1], [343, 7, 2*w^3 - 3*w^2 - 9*w + 6], [359, 359, -2*w^3 + 10*w - 1], [367, 367, -w^3 + 2*w^2 + w - 4], [367, 367, 3*w^3 - 11*w - 1], [373, 373, -w^3 + w^2 + 2*w - 5], [373, 373, 2*w^3 - 2*w^2 - 11*w - 1], [389, 389, -2*w^3 + 3*w^2 + 8*w - 6], [409, 409, 3*w^3 - 2*w^2 - 13*w - 1], [419, 419, 3*w^3 - w^2 - 12*w - 1], [419, 419, w^3 - w^2 - 4*w - 4], [439, 439, w^2 + 2*w - 4], [439, 439, 3*w^3 + w^2 - 11*w - 5], [443, 443, 2*w^3 + 2*w^2 - 7*w - 8], [449, 449, 4*w^3 - w^2 - 16*w - 8], [457, 457, 2*w^3 + w^2 - 11*w - 4], [461, 461, -5*w^3 + 2*w^2 + 24*w + 2], [463, 463, -w^3 + 3*w^2 + 6*w - 5], [467, 467, w^3 - 3*w^2 - 6*w + 4], [467, 467, 3*w^3 - w^2 - 12*w - 2], [479, 479, -w^3 + w^2 + 4*w - 6], [479, 479, -w^3 + 2*w + 8], [491, 491, -w^3 + 2*w^2 + 2*w - 6], [491, 491, w - 5], [499, 499, 2*w^3 + w^2 - 10*w - 4], [509, 509, -4*w^3 + w^2 + 20*w + 5], [521, 521, w^3 - w + 6], [523, 523, -4*w^3 + 18*w + 5], [523, 523, -2*w^3 - 2*w^2 + 9*w + 12], [557, 557, w^2 - 3*w - 6], [571, 571, 3*w^3 - 11*w - 8], [577, 577, 2*w^3 + 2*w^2 - 11*w - 7], [577, 577, -3*w^3 + 4*w^2 + 11*w - 6], [587, 587, -w^3 - w^2 + 7*w + 11], [593, 593, w^3 + w^2 - 8*w - 8], [593, 593, -2*w^3 + 4*w^2 + 6*w - 9], [599, 599, 4*w^3 - 17*w - 9], [599, 599, w^3 + w^2 - 6*w - 10], [601, 601, 3*w^2 - 10], [607, 607, 4*w^3 - w^2 - 18*w - 8], [619, 619, w^2 - w - 8], [641, 641, -w^3 + 3*w^2 + 2*w - 10], [643, 643, 3*w^3 - w^2 - 16*w + 1], [653, 653, -2*w^3 + 2*w^2 + 9*w + 3], [677, 677, w^3 + w^2 - 8*w - 11], [677, 677, 2*w^3 - w^2 - 12*w - 3], [683, 683, 3*w^3 - 2*w^2 - 13*w - 2], [683, 683, 3*w^3 + 2*w^2 - 16*w - 10], [691, 691, -2*w^3 - 2*w^2 + 12*w + 15], [691, 691, 3*w^3 - 2*w^2 - 15*w - 2], [691, 691, w^3 - 2*w^2 - 6*w + 6], [691, 691, -4*w^3 + 3*w^2 + 15*w - 2], [719, 719, 2*w^3 - 7*w - 8], [719, 719, w^2 + 2*w - 5], [727, 727, -w^3 + 3*w^2 + 4*w - 8], [727, 727, 2*w^3 - 9*w - 9], [733, 733, w^3 - 8*w - 2], [739, 739, -w^3 - 2*w^2 + 4*w + 10], [743, 743, w^3 - w^2 - 2*w + 8], [743, 743, 4*w^3 - w^2 - 17*w - 4], [751, 751, -2*w^3 + 2*w^2 + 6*w - 5], [751, 751, w^3 - 5*w - 7], [769, 769, 3*w^3 - 2*w^2 - 10*w], [787, 787, -2*w^3 + 3*w^2 + 8*w], [787, 787, 3*w^3 - w^2 - 10*w - 4], [809, 809, 3*w^3 + w^2 - 16*w - 6], [811, 811, 3*w^3 - 14*w - 2], [811, 811, -w^3 + 3*w^2 + 5*w - 5], [811, 811, w^3 - 2*w - 6], [811, 811, 3*w^3 - w^2 - 11*w - 3], [823, 823, w^3 + 2*w^2 - 3*w - 8], [827, 827, -w^3 + 3*w^2 + 3*w - 7], [829, 829, w^3 + w^2 - 3*w - 7], [853, 853, 3*w^3 + w^2 - 14*w - 6], [857, 857, 3*w^3 + w^2 - 13*w - 5], [857, 857, 3*w^3 - 3*w^2 - 11*w - 1], [859, 859, 4*w^3 - 2*w^2 - 18*w - 3], [859, 859, 3*w^3 - 11*w - 3], [863, 863, 3*w^3 + w^2 - 17*w - 9], [877, 877, -w^3 - 2*w^2 + 9*w + 1], [877, 877, 5*w^3 + w^2 - 23*w - 11], [911, 911, w^2 - 4*w - 6], [911, 911, -2*w^3 + 2*w^2 + 10*w + 3], [919, 919, -4*w^3 + 3*w^2 + 18*w - 1], [929, 929, 2*w^3 - 13*w - 12], [929, 929, -w^3 + 2*w^2 + 7*w - 5], [953, 953, -3*w^3 + 3*w^2 + 13*w - 1], [967, 967, -3*w^3 + 4*w^2 + 13*w - 7], [971, 971, 2*w^2 - 3*w - 12], [971, 971, 3*w^3 - w^2 - 16*w - 3]]; primes := [ideal : I in primesArray]; heckePol := x^4 - x^3 - 11*x^2 + 9*x + 10; K := NumberField(heckePol); heckeEigenvaluesArray := [e, 1, 1, -1/2*e^3 + 11/2*e - 1, 1/2*e^3 - 7/2*e - 1, -2, 1/2*e^3 - e^2 - 9/2*e + 5, 2*e + 2, -1/2*e^3 - e^2 + 9/2*e + 3, 1/2*e^3 - e^2 - 9/2*e + 9, -1/2*e^3 + 11/2*e - 1, 1/2*e^3 - e^2 - 13/2*e + 9, 0, 2, 2, -e^3 + e^2 + 6*e - 8, e^3 - 11*e + 4, -2*e^2 + 12, -2*e^2 + 14, -1/2*e^3 + e^2 + 13/2*e - 13, -1/2*e^3 + 3*e^2 + 5/2*e - 19, -2*e^3 + 16*e - 2, 2*e^2 - 2*e - 12, 1/2*e^3 + e^2 - 5/2*e - 3, -e^3 + 2*e^2 + 11*e - 8, -e^3 - 2*e^2 + 9*e + 8, e^2 - 3*e - 2, -3/2*e^3 + e^2 + 31/2*e - 5, -e^3 + 7*e + 8, 1/2*e^3 - 15/2*e + 3, 2*e^3 - 18*e + 4, -1/2*e^3 + e^2 + 9/2*e - 1, 1/2*e^3 - 11/2*e - 1, -e^3 + 5*e + 4, 2*e^3 - 18*e + 8, -e^3 - 2*e^2 + 11*e + 8, -e^3 + 2*e^2 + 9*e - 2, -e^3 - 2*e^2 + 7*e + 8, -3*e^2 - e + 20, e^3 - 11*e + 4, 2*e^3 - 18*e + 2, e^3 + 2*e^2 - 9*e - 18, -e^3 + 11*e + 2, -e^3 + 2*e^2 + 13*e - 16, -e^3 + 7*e + 8, -1/2*e^3 - e^2 - 3/2*e + 13, e^3 - 2*e^2 - 9*e + 10, e^3 - 3*e^2 - 8*e + 24, -1/2*e^3 + 3/2*e - 7, -1/2*e^3 + 19/2*e - 5, 2*e^3 - 16*e + 4, -2*e^2 + 2*e + 20, e^3 - 13*e + 12, -e^3 + 2*e^2 + 9*e - 12, 2*e^3 - 2*e^2 - 12*e + 18, -e^2 - 3*e - 6, 1/2*e^3 + 3*e^2 - 5/2*e - 15, 1/2*e^3 - 2*e^2 - 11/2*e + 15, -e^3 + e^2 + 14*e - 8, -e^3 - 4*e^2 + 7*e + 28, 1/2*e^3 + 4*e^2 - 15/2*e - 17, e^3 + 2*e^2 - 13*e - 8, -3*e^3 + 25*e - 6, -e^3 + 5*e + 4, 2*e^3 - 4*e^2 - 22*e + 14, -1/2*e^3 - e^2 + 5/2*e + 9, -e^3 + 5*e + 12, e^2 + 3*e - 16, -e^3 + 4*e^2 + 5*e - 26, 3/2*e^3 - e^2 - 31/2*e + 7, 1/2*e^3 - 3/2*e + 7, -2*e^3 + 18*e - 16, e^3 + 2*e^2 - 7*e, 3*e^2 + e - 22, -e^3 + 4*e^2 + 7*e - 22, 2*e^3 - 14*e - 6, -5/2*e^3 + 3*e^2 + 53/2*e - 21, -8*e - 10, 3*e^3 - e^2 - 32*e + 10, -1/2*e^3 - e^2 + 21/2*e - 5, -2*e^3 + 2*e^2 + 18*e - 10, -e^3 + 2*e^2 + 7*e, -2*e^2 - 6*e + 20, e^3 - 6*e^2 - 9*e + 34, e^3 + 2*e^2 - 7*e - 10, e^3 + 2*e^2 - 13*e + 8, 2*e^3 + 2*e^2 - 24*e + 2, e^3 + 2*e^2 - 5*e - 6, e^3 - 2*e^2 - 13*e + 18, 1/2*e^3 - 11/2*e - 17, 2*e^3 - 28*e + 10, e^3 + 2*e^2 - 13*e - 30, 1/2*e^3 + e^2 - 21/2*e - 23, 3/2*e^3 - 25/2*e - 3, 7/2*e^3 - 3*e^2 - 63/2*e + 15, 3/2*e^3 + 3*e^2 - 23/2*e - 15, -e^3 - e^2 + 22*e + 12, 7/2*e^3 - 5*e^2 - 75/2*e + 19, e^3 - 5*e - 16, 5/2*e^3 - 35/2*e + 3, 2*e^2 - 10*e - 8, -e^3 - 2*e^2 + 13*e + 8, -3*e^3 - 2*e^2 + 33*e - 2, -5/2*e^3 + 47/2*e + 13, e^3 + 6*e^2 - 13*e - 36, e^3 - 2*e^2 - 9*e + 24, e^3 - 11*e + 10, 3*e^3 + e^2 - 30*e, -2*e^2 - 12*e + 12, -e^3 + 2*e^2 + e - 2, 1/2*e^3 - 3*e^2 - 5/2*e + 5, 2*e^3 - 20*e - 8, 2*e^3 + 4*e^2 - 16*e - 26, 3*e^3 - 4*e^2 - 21*e + 24, -3/2*e^3 - e^2 + 31/2*e - 27, e^3 - 2*e^2 - 5*e + 28, -e^3 + 9*e + 4, -3*e^3 + 27*e + 4, -1/2*e^3 - 2*e^2 - 9/2*e + 37, 5/2*e^3 - 5*e^2 - 29/2*e + 37, 3/2*e^3 + 2*e^2 - 37/2*e - 23, -2*e^3 + 2*e^2 + 18*e - 18, 2*e^3 - 4*e^2 - 16*e + 10, -e^3 + 19*e + 10, e^3 + 6*e^2 - 9*e - 22, -2*e^3 + 2*e^2 + 24*e - 12, -3/2*e^3 - e^2 + 27/2*e + 19, -1/2*e^3 - 2*e^2 - 1/2*e + 5, 4*e^3 - 32*e + 4, -e^3 + 2*e^2 + 17*e - 26, -2*e^3 + 5*e^2 + 21*e - 38, -3*e^3 - 4*e^2 + 23*e + 32, -e^3 + 3*e, 4*e^3 - 2*e^2 - 34*e - 12, 4*e^3 - 4*e^2 - 36*e + 28, -3*e^3 + 4*e^2 + 29*e - 20, 2*e^3 - 4*e^2 - 14*e + 32, -3/2*e^3 + 6*e^2 + 37/2*e - 33, 1/2*e^3 + e^2 - 13/2*e + 17, -7/2*e^3 + 61/2*e - 33, -e^3 - 2*e^2 + 7*e + 4, -2*e^3 + 28*e - 2, -3/2*e^3 - 3*e^2 + 39/2*e - 5, e^3 - 4*e^2 - 15*e + 44, -e^3 + 8*e^2 + 11*e - 32, 2*e^2 + 4*e - 12, -5/2*e^3 + 2*e^2 + 75/2*e - 15, -2*e^3 + 22*e - 40, e^3 - 4*e^2 - 7*e + 34, -3*e^3 + 2*e^2 + 27*e - 12, -16*e - 2, 5*e^3 - 4*e^2 - 41*e + 32, 2*e^3 - 3*e^2 - 11*e + 22, e^3 + 3*e^2 - 2*e, 2*e^3 - 8*e^2 - 10*e + 50, -e^3 - 4*e^2 + 19*e + 20, -3*e^3 + 4*e^2 + 33*e - 36, e^3 + 2*e^2 - 13*e + 18, 2*e^2 + 12*e - 18, -2*e^3 + 6*e^2 + 22*e - 38]; heckeEigenvalues := AssociativeArray(); for i := 1 to #heckeEigenvaluesArray do heckeEigenvalues[primes[i]] := heckeEigenvaluesArray[i]; end for; ALEigenvalues := AssociativeArray(); ALEigenvalues[ideal] := -1; 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;