/* 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![-55, 0, 1]; F := NumberField(g); ZF := Integers(F); NN := ideal; primesArray := [ [2, 2, w + 1], [3, 3, w + 1], [3, 3, w + 2], [5, 5, -2*w + 15], [11, 11, 3*w - 22], [13, 13, w + 4], [13, 13, w + 9], [17, 17, w + 2], [17, 17, w + 15], [19, 19, -w - 6], [19, 19, w - 6], [23, 23, w + 3], [23, 23, w + 20], [47, 47, w + 14], [47, 47, w + 33], [49, 7, -7], [67, 67, w + 16], [67, 67, w + 51], [73, 73, w + 36], [73, 73, w + 37], [79, 79, 5*w + 36], [79, 79, 5*w - 36], [89, 89, -w - 12], [89, 89, w - 12], [103, 103, w + 40], [103, 103, w + 63], [131, 131, -6*w - 43], [131, 131, -6*w + 43], [139, 139, 2*w - 9], [139, 139, -2*w - 9], [151, 151, 4*w - 27], [151, 151, 4*w + 27], [163, 163, w + 50], [163, 163, w + 113], [173, 173, w + 48], [173, 173, w + 125], [181, 181, -3*w - 26], [181, 181, 3*w - 26], [193, 193, w + 21], [193, 193, w + 172], [197, 197, w + 45], [197, 197, w + 152], [211, 211, 2*w - 3], [211, 211, -2*w - 3], [223, 223, w + 72], [223, 223, w + 151], [229, 229, 6*w + 47], [229, 229, 6*w - 47], [233, 233, w + 88], [233, 233, w + 145], [239, 239, -3*w - 16], [239, 239, 3*w - 16], [269, 269, -w - 18], [269, 269, w - 18], [271, 271, -8*w - 57], [271, 271, -8*w + 57], [277, 277, w + 71], [277, 277, w + 206], [293, 293, w + 73], [293, 293, w + 220], [337, 337, w + 27], [337, 337, w + 310], [359, 359, 9*w + 64], [359, 359, 9*w - 64], [367, 367, w + 34], [367, 367, w + 333], [373, 373, w + 146], [373, 373, w + 227], [383, 383, w + 173], [383, 383, w + 210], [389, 389, -5*w - 42], [389, 389, 5*w - 42], [401, 401, 29*w - 216], [401, 401, 11*w - 84], [421, 421, -6*w + 49], [421, 421, -6*w - 49], [431, 431, 3*w - 8], [431, 431, -3*w - 8], [439, 439, -4*w - 21], [439, 439, 4*w - 21], [443, 443, w + 99], [443, 443, w + 344], [449, 449, -8*w - 63], [449, 449, -8*w + 63], [457, 457, w + 91], [457, 457, w + 366], [463, 463, w + 38], [463, 463, w + 425], [467, 467, w + 191], [467, 467, w + 276], [479, 479, -3*w - 4], [479, 479, 3*w - 4], [487, 487, w + 223], [487, 487, w + 264], [491, 491, 3*w - 2], [491, 491, -3*w - 2], [509, 509, 2*w - 27], [509, 509, -2*w - 27], [521, 521, -w - 24], [521, 521, w - 24], [557, 557, w + 75], [557, 557, w + 482], [571, 571, 11*w + 78], [571, 571, 11*w - 78], [587, 587, w + 246], [587, 587, w + 341], [593, 593, w + 184], [593, 593, w + 409], [613, 613, w + 235], [613, 613, w + 378], [641, 641, -4*w - 39], [641, 641, 4*w - 39], [643, 643, w + 174], [643, 643, w + 469], [647, 647, w + 257], [647, 647, w + 390], [659, 659, -18*w + 131], [659, 659, 30*w - 221], [661, 661, 3*w - 34], [661, 661, -3*w - 34], [673, 673, w + 196], [673, 673, w + 477], [677, 677, w + 240], [677, 677, w + 437], [683, 683, w + 136], [683, 683, w + 547], [709, 709, 21*w - 158], [709, 709, 27*w - 202], [727, 727, w + 339], [727, 727, w + 388], [733, 733, w + 39], [733, 733, w + 694], [739, 739, 10*w - 69], [739, 739, 10*w + 69], [811, 811, 35*w - 258], [811, 811, -19*w + 138], [823, 823, w + 177], [823, 823, w + 646], [829, 829, -6*w - 53], [829, 829, 6*w - 53], [841, 29, -29], [853, 853, w + 316], [853, 853, w + 537], [857, 857, w + 270], [857, 857, w + 587], [863, 863, w + 405], [863, 863, w + 458], [877, 877, w + 377], [877, 877, w + 500], [881, 881, -19*w + 144], [881, 881, -37*w + 276], [883, 883, w + 52], [883, 883, w + 831], [907, 907, w + 350], [907, 907, w + 557], [919, 919, -8*w - 51], [919, 919, 8*w - 51], [929, 929, 5*w - 48], [929, 929, -5*w - 48], [937, 937, w + 176], [937, 937, w + 761], [947, 947, w + 252], [947, 947, w + 695], [953, 953, w + 334], [953, 953, w + 619], [961, 31, -31], [983, 983, w + 277], [983, 983, w + 706], [997, 997, w + 371], [997, 997, w + 626]]; primes := [ideal : I in primesArray]; heckePol := x^4 - 5*x^2 + x + 4; K := NumberField(heckePol); heckeEigenvaluesArray := [1, 1, e, -e^3 - e^2 + 4*e + 1, -e^2 + 5, -e^2 + e + 3, e^3 + e^2 - 5*e, 2*e^3 - e^2 - 7*e + 3, -e^3 + e^2 + 6*e - 4, e^2 + e, -4*e^3 - 2*e^2 + 13*e + 3, 3*e^3 + 4*e^2 - 10*e - 8, e^3 - 2*e^2 - 3*e + 4, 2*e^3 + e^2 - 7*e + 1, -2*e^3 - 5*e^2 + 3*e + 14, 2*e^3 + 5*e^2 - 8*e - 11, 3*e^3 + 10*e^2 - 8*e - 22, 3*e^3 + 2*e^2 - 10*e - 1, 7*e^3 + 5*e^2 - 19*e - 10, e^3 + 7*e^2 - 3*e - 21, e^2 + 4*e + 2, 5*e^3 + 7*e^2 - 16*e - 12, 3*e^3 - 8*e - 1, -6*e^3 - 7*e^2 + 16*e + 16, -6*e^3 - 5*e^2 + 20*e + 5, -6*e^3 - e^2 + 17*e - 1, -e^2 - 2*e + 18, e^2 - 5*e - 2, -5*e^3 - 13*e^2 + 9*e + 34, 3*e^3 - 14*e + 4, 5*e^3 - 2*e^2 - 18*e + 5, -2*e^3 - e^2 + 7*e + 15, -9*e^2 + e + 28, -4*e^3 - 6*e^2 + 5*e + 13, -12*e^3 - 10*e^2 + 36*e + 15, 2*e^3 + 4*e^2 - 7*e - 13, 7*e^3 + 10*e^2 - 19*e - 28, 2*e^2 - 6*e - 10, 6*e^3 + 5*e^2 - 21*e - 2, -e^2 - 7*e + 8, -4*e^3 + 2*e^2 + 14*e - 2, e^3 + 5*e^2 - 4*e - 22, 3*e^3 + 15*e^2 - 11*e - 38, -5*e^3 - 11*e^2 + 8*e + 32, 3*e^3 - 2*e^2 - 5*e + 15, e^3 - 9*e^2 - 5*e + 25, -5*e^3 - 10*e^2 + 15*e + 29, e^3 + 11*e^2 - 5*e - 36, -7*e^3 - 14*e^2 + 24*e + 28, 4*e^3 - 8*e^2 - 18*e + 17, -2*e^3 + 6*e - 1, e^3 + 5*e^2 + 3*e - 8, -6*e^3 + e^2 + 22*e - 2, 2*e^3 + 9*e^2 - 7*e - 20, 10*e^3 + 3*e^2 - 25*e + 6, -2*e^3 + 3*e^2 + 9*e - 6, -7*e^3 - 7*e^2 + 24*e + 6, 11*e^3 + 11*e^2 - 32*e - 14, -5*e^3 - 18*e^2 + 8*e + 42, -e^3 - 3*e^2 + 7*e + 10, e^3 + 18*e^2 + e - 41, -11*e^3 - 18*e^2 + 30*e + 37, -5*e^3 + 17*e + 14, -4*e^2 + 6*e + 9, 4*e^3 - e^2 - 19*e + 20, 5*e^3 + 15*e^2 - 3*e - 42, -4*e^3 - 2*e^2 + 3*e + 6, -4*e^3 - 11*e^2 + e + 43, -13*e^3 - e^2 + 43*e + 2, 3*e^3 + 7*e^2 - 15*e - 21, 3*e^3 + 11*e^2 - 11*e - 26, 3*e^3 + 4*e^2 - 20*e - 16, -3*e^3 - 7*e^2 + 10*e + 22, e^3 + 2*e^2 - 14*e - 6, -3*e^3 + 8*e^2 + 20*e - 8, -e^3 - 11*e^2 - 5*e + 38, 9*e^3 + 8*e^2 - 38*e - 5, -4*e^3 + 2*e^2 + 18*e - 14, -5*e^3 + 3*e^2 + 15*e - 15, -4*e^2 + 8*e + 12, -e^3 - e^2 + 9*e + 5, 4*e^3 + 13*e^2 - e - 39, 7*e^2 - e - 3, -9*e^3 - 17*e^2 + 30*e + 28, 5*e^3 - 3*e^2 - 14*e + 12, 8*e^2 + 5*e - 12, 5*e^3 + 3*e^2 - 20*e - 8, -12*e^3 - 7*e^2 + 44*e - 5, -9*e^2 + 5*e + 17, -3*e^3 - 4*e^2 - e + 15, 6*e^3 + 3*e^2 - 32*e - 8, 9*e^3 + 8*e^2 - 35*e - 15, -8*e^3 + e^2 + 22*e - 24, -4*e^3 - 11*e^2 + 27*e + 30, -e^3 - 12*e^2 - 12*e + 37, 10*e^3 + 14*e^2 - 34*e - 29, 10*e^3 + 3*e^2 - 28*e - 20, 3*e^3 - 6*e^2 - 15*e + 14, -6*e^3 - 15*e^2 + 8*e + 56, -3*e^3 - e^2 + 20*e + 6, -10*e^3 - 17*e^2 + 32*e + 31, -7*e^3 - 5*e^2 + 20*e - 6, -6*e^3 - 4*e^2 + 28*e + 11, -9*e^3 - 17*e^2 + 20*e + 52, -7*e^3 - 7*e^2 + 27*e + 5, 15*e^3 + 16*e^2 - 50*e - 37, 2*e^3 + 16*e^2 - 4*e - 50, -5*e^3 - 3*e^2 + 25*e - 12, -15*e^3 - 23*e^2 + 39*e + 61, -3*e^3 + 7*e^2 + 8*e - 28, 2*e^2 + 13*e - 17, 3*e^3 + 3*e + 24, e^2 - 7*e - 34, 16*e^3 + 10*e^2 - 53*e - 29, 4*e^3 + 7*e^2 - 23*e + 4, -9*e^3 - 7*e^2 + 24*e + 21, 10*e^3 - 28*e - 6, 6*e^3 + 27*e^2 - 14*e - 54, -e^3 + 12*e^2 + 12*e - 20, -4*e^3 + 5*e^2 + 27*e - 29, -4*e^3 + 9*e^2 + 18*e - 22, e^3 + 10*e^2 - 17*e - 34, 6*e^3 + 11*e^2 - 24*e - 16, -15*e^3 - 7*e^2 + 49*e - 10, 12*e^3 + 11*e^2 - 30*e - 25, -5*e^3 - 9*e^2 + 8*e + 12, -20*e^3 - 9*e^2 + 63*e + 19, 8*e^3 + 5*e^2 - 17*e + 2, 6*e^3 + e^2 - 12*e + 8, -16*e^3 - 21*e^2 + 56*e + 24, -14*e^3 - 9*e^2 + 41*e, -3*e^3 - 9*e^2 - 4*e + 51, 3*e^3 + e^2 - 30*e + 8, -3*e^3 + 2*e^2 + 20*e - 8, 4*e^2 - 4*e + 5, -14*e^3 - 9*e^2 + 48*e + 4, 9*e^3 + 2*e^2 - 35*e + 11, -8*e^3 - 10*e^2 + 19*e + 40, e^3 + 11*e^2 + 13*e - 14, 14*e^3 + 20*e^2 - 37*e - 54, 22*e^3 + 8*e^2 - 73*e - 11, 5*e^3 + 7*e^2 - 27*e - 22, 20*e^3 + 16*e^2 - 47*e - 34, -3*e^3 - 16*e^2 + 8*e + 32, 4*e^3 - 14*e^2 - 21*e + 13, 16*e^3 - 55*e - 9, 3*e^3 - 18, -9*e^3 - 4*e^2 + 26*e + 34, 4*e^2 - 8*e - 28, 2*e^3 - 4*e^2 - 15*e + 4, -2*e^3 + 11*e^2 + 29*e - 41, -e^3 + 23*e^2 + 17*e - 40, e^3 + 11*e^2 + 5*e - 20, -20*e^3 - 19*e^2 + 65*e + 24, 18*e^3 + 26*e^2 - 44*e - 70, -3*e^3 + 11*e^2 + 34*e - 28, 7*e^3 + 21*e^2 - 21*e - 33, 7*e^3 - 16*e^2 - 19*e + 55, -18*e^3 - 16*e^2 + 59*e + 32, 8*e^3 + 8*e^2 - 30*e + 4, -10*e^3 - 12*e^2 + 23*e + 22, -8*e^3 + 46*e - 12, -11*e^3 - 28*e^2 + 32*e + 40, -7*e - 30, 6*e^3 + 11*e^2 - 29*e - 42, -19*e^3 - 10*e^2 + 60*e + 5, -14*e^3 - 22*e^2 + 48*e + 16, 8*e^3 + 23*e^2 - 32*e - 44, -8*e^3 - 26*e^2 + 15*e + 72, 4*e^3 - 3*e^2 + 6*e + 7]; 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;