/* 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![3, 2, -5, -2, 1]; F := NumberField(g); ZF := Integers(F); NN := ideal; primesArray := [ [3, 3, w], [4, 2, -w^3 + 3*w^2 + w - 2], [11, 11, -w^3 + 3*w^2 + 2*w - 5], [13, 13, w^3 - 2*w^2 - 4*w + 2], [13, 13, -w + 2], [17, 17, w^3 - 3*w^2 - 2*w + 2], [19, 19, -w^2 + w + 4], [19, 19, w^3 - 2*w^2 - 3*w + 2], [23, 23, w^2 - 2*w - 1], [27, 3, w^3 - 2*w^2 - 5*w - 1], [29, 29, -w^3 + 2*w^2 + 5*w - 1], [37, 37, -w^3 + 2*w^2 + 5*w - 4], [41, 41, 2*w^3 - 5*w^2 - 6*w + 4], [53, 53, w^3 - 2*w^2 - 3*w - 2], [59, 59, w - 4], [67, 67, 2*w^2 - 3*w - 8], [73, 73, 2*w^3 - 5*w^2 - 6*w + 5], [89, 89, -2*w^3 + 6*w^2 + 5*w - 7], [97, 97, -2*w^3 + 6*w^2 + 3*w - 7], [97, 97, -w^3 + 3*w^2 + 3*w - 1], [103, 103, w^2 - 4*w - 4], [113, 113, 2*w^3 - 5*w^2 - 4*w + 1], [113, 113, -w^3 + 3*w^2 + w - 5], [139, 139, 2*w^2 - 3*w - 4], [139, 139, w^3 - w^2 - 6*w - 1], [149, 149, 2*w^3 - 5*w^2 - 5*w + 2], [149, 149, w^3 - 4*w^2 + 10], [151, 151, -3*w - 1], [157, 157, w^2 - w - 8], [157, 157, w^3 - 7*w - 8], [163, 163, -3*w^3 + 8*w^2 + 8*w - 10], [163, 163, w^3 - 3*w^2 - 4*w + 7], [163, 163, -w^3 + 4*w^2 + w - 8], [163, 163, -2*w^3 + 5*w^2 + 7*w - 4], [167, 167, -2*w^3 + 5*w^2 + 8*w - 4], [169, 13, -2*w^3 + 4*w^2 + 7*w - 5], [173, 173, 2*w^3 - 4*w^2 - 9*w + 4], [173, 173, -w^3 + 5*w^2 - 2*w - 5], [181, 181, 3*w^3 - 7*w^2 - 12*w + 7], [191, 191, w^3 - 3*w^2 - 3*w - 1], [199, 199, 2*w^3 - 3*w^2 - 10*w - 1], [199, 199, 2*w^3 - 6*w^2 - 6*w + 13], [223, 223, -2*w^3 + 6*w^2 + 4*w - 11], [223, 223, 3*w^3 - 7*w^2 - 12*w + 8], [223, 223, -2*w^3 + 5*w^2 + 6*w - 1], [229, 229, -w^3 + 3*w^2 + 2*w + 1], [229, 229, 3*w^3 - 4*w^2 - 15*w - 5], [233, 233, -3*w^3 + 7*w^2 + 11*w - 5], [233, 233, 2*w^3 - 5*w^2 - 4*w + 5], [241, 241, w^3 - 3*w^2 - 5*w + 7], [257, 257, w^3 - 3*w^2 - 4*w + 8], [263, 263, w^2 - 4*w - 5], [271, 271, -2*w^3 + 6*w^2 + 5*w - 13], [277, 277, -2*w^3 + 6*w^2 + 3*w - 8], [277, 277, w^3 - 2*w^2 - 2*w - 2], [281, 281, 2*w^3 - 5*w^2 - 4*w + 2], [283, 283, -3*w^2 + 7*w + 10], [283, 283, -w^3 + 4*w^2 - w - 7], [293, 293, 2*w^3 - 5*w^2 - 3*w + 4], [293, 293, w^3 - 8*w - 4], [307, 307, -w^3 + 2*w^2 + 6*w - 2], [311, 311, w^2 - 5], [317, 317, -w^3 + 5*w^2 - 2*w - 11], [331, 331, -w^3 + 3*w^2 - 5], [349, 349, -2*w^2 + 5*w + 2], [353, 353, -2*w^3 + 5*w^2 + 4*w - 4], [353, 353, 3*w^3 - 7*w^2 - 10*w + 2], [353, 353, -2*w^3 + 7*w^2 + 2*w - 10], [353, 353, w^3 + w^2 - 9*w - 13], [361, 19, -w^3 + w^2 + 5*w - 1], [373, 373, -w^3 + 3*w^2 + 4*w - 11], [373, 373, 2*w^3 - 5*w^2 - 5*w - 2], [383, 383, w^3 - 5*w^2 + w + 13], [389, 389, 3*w^3 - 10*w^2 - 4*w + 16], [397, 397, -w^3 + 2*w^2 + 3*w + 5], [397, 397, -3*w^3 + 7*w^2 + 10*w - 7], [419, 419, -w^3 + 2*w^2 + 4*w + 4], [419, 419, 3*w^3 - 7*w^2 - 12*w + 5], [421, 421, -w^2 + 5*w - 2], [421, 421, 3*w^3 - 7*w^2 - 10*w + 5], [431, 431, w^2 - 10], [439, 439, w^3 - w^2 - 7*w - 7], [461, 461, -2*w^3 + 7*w^2 + 5*w - 10], [467, 467, -3*w^3 + 6*w^2 + 14*w - 4], [479, 479, 3*w^2 - 6*w - 5], [479, 479, -4*w^3 + 11*w^2 + 10*w - 10], [491, 491, -w^3 + w^2 + 6*w - 1], [499, 499, -4*w^3 + 9*w^2 + 15*w - 10], [499, 499, 2*w^3 - 5*w^2 - 7*w + 2], [503, 503, -2*w^3 + 7*w^2 - 8], [521, 521, 2*w^2 - w - 7], [521, 521, -3*w^3 + 7*w^2 + 11*w - 11], [569, 569, 2*w^2 - 5*w - 1], [569, 569, -4*w - 1], [571, 571, -w^3 + 3*w^2 - 7], [577, 577, -w^3 + w^2 + 8*w - 4], [587, 587, -3*w^3 + 8*w^2 + 7*w - 8], [593, 593, 3*w^2 - 4*w - 11], [593, 593, -3*w^3 + 9*w^2 + 6*w - 14], [601, 601, -3*w^3 + 9*w^2 + 4*w - 10], [601, 601, 5*w^3 - 9*w^2 - 24*w - 2], [607, 607, 2*w^2 - 7*w - 5], [613, 613, w^3 - 6*w - 2], [613, 613, -w^2 + 3*w + 8], [617, 617, -w^2 + 4*w - 5], [619, 619, 3*w^3 - 6*w^2 - 13*w + 5], [625, 5, -5], [631, 631, -2*w^3 + 4*w^2 + 8*w - 7], [647, 647, -2*w^3 + 4*w^2 + 5*w - 1], [647, 647, w^3 - 3*w^2 - 2*w - 2], [653, 653, w^3 - 4*w^2 - w + 13], [653, 653, w^3 - 2*w^2 - 7*w + 5], [659, 659, -4*w^3 + 10*w^2 + 15*w - 14], [659, 659, 5*w^3 - 12*w^2 - 17*w + 14], [661, 661, w^2 - 5*w - 2], [661, 661, -w^3 + 5*w^2 - 2*w - 7], [673, 673, -w^3 + w^2 + 6*w - 2], [683, 683, 2*w^3 - 8*w^2 + w + 8], [683, 683, 5*w^3 - 12*w^2 - 19*w + 14], [701, 701, -2*w^3 + 6*w^2 + 5*w - 4], [709, 709, -w^2 + 3*w - 4], [709, 709, -2*w^3 + 5*w^2 + 9*w - 8], [719, 719, w^2 - 7], [719, 719, -2*w^3 + 3*w^2 + 8*w + 5], [733, 733, -2*w^3 + 7*w^2 + 3*w - 10], [739, 739, 4*w^3 - 11*w^2 - 13*w + 14], [739, 739, -5*w^3 + 10*w^2 + 21*w - 4], [739, 739, 3*w^3 - 8*w^2 - 6*w + 8], [739, 739, -w^3 + w^2 + 8*w - 5], [743, 743, -w - 5], [743, 743, w^3 - w^2 - 8*w - 8], [751, 751, -2*w^3 + 5*w^2 + 8*w - 2], [751, 751, -2*w^3 + 6*w^2 - 1], [757, 757, -2*w^3 + 6*w^2 + 3*w - 10], [757, 757, 5*w^2 - 9*w - 22], [761, 761, -2*w^3 + 4*w^2 + 9*w - 7], [761, 761, 2*w^3 - 3*w^2 - 12*w - 1], [769, 769, 5*w^3 - 13*w^2 - 14*w + 10], [773, 773, -3*w^3 + 5*w^2 + 16*w + 1], [773, 773, w^3 - 11*w + 2], [787, 787, -w^3 + 4*w^2 - w - 11], [797, 797, -5*w^3 + 12*w^2 + 17*w - 11], [809, 809, -2*w^3 + 7*w^2 + 4*w - 11], [809, 809, 4*w^3 - 9*w^2 - 14*w + 4], [821, 821, -w^3 + 5*w^2 - 2*w - 17], [827, 827, -3*w^3 + 8*w^2 + 9*w - 7], [829, 829, 2*w^3 - 6*w^2 - 5*w + 2], [829, 829, -w^3 + 4*w^2 - w - 10], [839, 839, w^2 - 8], [853, 853, -5*w^3 + 12*w^2 + 18*w - 16], [853, 853, w^3 - 6*w - 8], [863, 863, 5*w^3 - 11*w^2 - 19*w + 7], [881, 881, -3*w^3 + 9*w^2 + 9*w - 11], [907, 907, -w^3 + 2*w^2 + 7*w - 4], [907, 907, -2*w^3 + 3*w^2 + 7*w + 4], [929, 929, -w^3 + 5*w^2 - 3*w - 11], [937, 937, 2*w^3 - 5*w^2 - 6*w + 11], [937, 937, -2*w^3 + 6*w^2 + 3*w - 11], [941, 941, -3*w^3 + 8*w^2 + 11*w - 8], [953, 953, -4*w^3 + 10*w^2 + 10*w - 13], [953, 953, w^3 - 5*w^2 - w + 13], [967, 967, 3*w^3 - 7*w^2 - 9*w + 7], [967, 967, -2*w^3 + 5*w^2 + 8*w + 1], [967, 967, 4*w^3 - 13*w^2 - 6*w + 20], [967, 967, -2*w^2 + 3*w + 13], [971, 971, -6*w^3 + 13*w^2 + 25*w - 8], [977, 977, w^3 - w^2 - 4*w - 10], [977, 977, 2*w^3 - 6*w^2 - 7*w + 13], [983, 983, -4*w^3 + 10*w^2 + 11*w - 13], [983, 983, -w^3 + 5*w^2 - w - 7], [983, 983, 3*w^3 - 9*w^2 - 7*w + 19], [983, 983, -2*w^3 + 3*w^2 + 10*w - 1], [997, 997, 5*w^3 - 12*w^2 - 17*w + 13], [997, 997, -2*w^3 + 3*w^2 + 13*w - 4], [997, 997, w^3 - 7*w - 2], [997, 997, w^3 - 9*w - 2]]; primes := [ideal : I in primesArray]; heckePol := x^6 - 19*x^4 + 116*x^2 - 225; K := NumberField(heckePol); heckeEigenvaluesArray := [e, 1/15*e^5 - 4/15*e^3 - 19/15*e, -1, 4/15*e^5 - 46/15*e^3 + 134/15*e, e^4 - 13*e^2 + 41, -2/3*e^5 + 26/3*e^3 - 82/3*e, e^4 - 12*e^2 + 34, -13/15*e^5 + 157/15*e^3 - 443/15*e, -11/15*e^5 + 149/15*e^3 - 481/15*e, -4/15*e^5 + 46/15*e^3 - 104/15*e, 2/3*e^5 - 26/3*e^3 + 79/3*e, -2/15*e^5 + 38/15*e^3 - 172/15*e, -16/15*e^5 + 169/15*e^3 - 371/15*e, -e^4 + 8*e^2 - 6, -2*e^4 + 29*e^2 - 96, 8, 14/15*e^5 - 206/15*e^3 + 694/15*e, -28/15*e^5 + 352/15*e^3 - 1028/15*e, e^4 - 13*e^2 + 37, 22/15*e^5 - 238/15*e^3 + 542/15*e, 3*e^4 - 42*e^2 + 132, -2/5*e^5 + 23/5*e^3 - 37/5*e, -3*e^4 + 37*e^2 - 99, -8*e^4 + 94*e^2 - 248, -2*e^3 + 16*e, -e^3 + 7*e, 2*e^4 - 27*e^2 + 96, 4/3*e^5 - 55/3*e^3 + 179/3*e, 8*e^4 - 97*e^2 + 270, 4*e^4 - 48*e^2 + 138, -2*e^5 + 22*e^3 - 52*e, 5*e^4 - 62*e^2 + 176, 6*e^4 - 78*e^2 + 234, -2/5*e^5 + 8/5*e^3 + 38/5*e, 6/5*e^5 - 64/5*e^3 + 156/5*e, -12/5*e^5 + 158/5*e^3 - 482/5*e, 4/3*e^5 - 58/3*e^3 + 191/3*e, 2*e^4 - 26*e^2 + 86, -28/15*e^5 + 322/15*e^3 - 818/15*e, -3*e^4 + 38*e^2 - 114, -6/5*e^5 + 64/5*e^3 - 141/5*e, -10*e^4 + 123*e^2 - 356, e^4 - 10*e^2 + 40, 6/5*e^5 - 59/5*e^3 + 81/5*e, -4/15*e^5 + 46/15*e^3 - 194/15*e, -4*e^4 + 48*e^2 - 128, 4/5*e^5 - 61/5*e^3 + 249/5*e, 32/15*e^5 - 353/15*e^3 + 787/15*e, -9/5*e^5 + 111/5*e^3 - 319/5*e, 2*e^4 - 21*e^2 + 54, 5*e^2 - 40, 3*e^2 - 12, -6*e^4 + 66*e^2 - 156, -4*e^2 + 26, -12*e^4 + 144*e^2 - 396, -56/15*e^5 + 644/15*e^3 - 1666/15*e, -e^4 + 15*e^2 - 39, 2*e^4 - 30*e^2 + 96, -34/15*e^5 + 436/15*e^3 - 1334/15*e, 26/15*e^5 - 374/15*e^3 + 1276/15*e, -10/3*e^5 + 124/3*e^3 - 350/3*e, -7*e^4 + 83*e^2 - 213, 8, 2*e^4 - 34*e^2 + 136, 3*e^5 - 37*e^3 + 109*e, 12/5*e^5 - 158/5*e^3 + 462/5*e, 22/15*e^5 - 208/15*e^3 + 392/15*e, 4*e^4 - 44*e^2 + 120, -2*e^4 + 38*e^2 - 150, -11/5*e^5 + 139/5*e^3 - 381/5*e, 12*e^4 - 132*e^2 + 310, 8*e^4 - 89*e^2 + 224, 10*e^4 - 126*e^2 + 376, -11*e^4 + 133*e^2 - 379, -4*e^4 + 45*e^2 - 118, 56/15*e^5 - 734/15*e^3 + 2266/15*e, 10*e^4 - 112*e^2 + 280, -26/15*e^5 + 344/15*e^3 - 1096/15*e, -2*e^5 + 24*e^3 - 67*e, 14/5*e^5 - 156/5*e^3 + 364/5*e, 11*e^4 - 143*e^2 + 435, -12*e^4 + 151*e^2 - 446, -4*e^4 + 30*e^2 - 14, 6/5*e^5 - 94/5*e^3 + 306/5*e, 58/15*e^5 - 742/15*e^3 + 2258/15*e, 7/3*e^5 - 97/3*e^3 + 323/3*e, 16/5*e^5 - 194/5*e^3 + 556/5*e, -34/15*e^5 + 361/15*e^3 - 809/15*e, -5*e^5 + 63*e^3 - 189*e, -7*e^4 + 85*e^2 - 243, -6*e^4 + 64*e^2 - 136, 14/15*e^5 - 146/15*e^3 + 229/15*e, -16/5*e^5 + 174/5*e^3 - 361/5*e, 16/3*e^5 - 196/3*e^3 + 563/3*e, -2*e^4 + 32*e^2 - 86, -3/5*e^5 + 27/5*e^3 - 33/5*e, 14/15*e^5 - 191/15*e^3 + 439/15*e, 16*e^4 - 190*e^2 + 518, e^4 - 17*e^2 + 29, -5*e^4 + 52*e^2 - 104, -6/5*e^5 + 94/5*e^3 - 341/5*e, -14/15*e^5 + 206/15*e^3 - 964/15*e, -4/5*e^5 + 56/5*e^3 - 244/5*e, -10*e^4 + 118*e^2 - 322, 6*e^4 - 84*e^2 + 268, 26/15*e^5 - 224/15*e^3 + 286/15*e, -11*e^4 + 134*e^2 - 364, 86/15*e^5 - 1064/15*e^3 + 3076/15*e, -26/15*e^5 + 269/15*e^3 - 541/15*e, -6*e^4 + 74*e^2 - 176, 20*e^2 - 126, 23/15*e^5 - 317/15*e^3 + 943/15*e, -14/15*e^5 + 146/15*e^3 - 124/15*e, 71/15*e^5 - 839/15*e^3 + 2251/15*e, 88/15*e^5 - 1027/15*e^3 + 2663/15*e, -e^4 + 18*e^2 - 74, 22/15*e^5 - 358/15*e^3 + 1412/15*e, -6*e^4 + 78*e^2 - 222, 92/15*e^5 - 1088/15*e^3 + 2902/15*e, 14/3*e^5 - 176/3*e^3 + 508/3*e, 5*e^4 - 48*e^2 + 100, 7/5*e^5 - 73/5*e^3 + 187/5*e, -4*e^4 + 48*e^2 - 104, 2*e^4 - 38*e^2 + 132, 2*e^2 + 2, 4/15*e^5 - 46/15*e^3 - 31/15*e, 28/15*e^5 - 352/15*e^3 + 878/15*e, 4/5*e^5 - 56/5*e^3 + 154/5*e, 37/5*e^5 - 463/5*e^3 + 1377/5*e, -e^4 + 25*e^2 - 135, 8*e^4 - 100*e^2 + 314, 82/15*e^5 - 1078/15*e^3 + 3392/15*e, 10*e^4 - 132*e^2 + 400, -4*e^4 + 62*e^2 - 236, 13*e^4 - 165*e^2 + 471, -14/3*e^5 + 176/3*e^3 - 508/3*e, -6/5*e^5 + 84/5*e^3 - 266/5*e, 22/5*e^5 - 283/5*e^3 + 907/5*e, 46/15*e^5 - 589/15*e^3 + 1751/15*e, 32/15*e^5 - 518/15*e^3 + 1942/15*e, 5*e^4 - 65*e^2 + 205, -14/3*e^5 + 182/3*e^3 - 532/3*e, -4*e^4 + 44*e^2 - 134, -8/3*e^5 + 110/3*e^3 - 358/3*e, 6*e^4 - 60*e^2 + 120, -16/15*e^5 + 109/15*e^3 + 139/15*e, -83/15*e^5 + 1037/15*e^3 - 3073/15*e, -8*e^4 + 95*e^2 - 280, 5*e^4 - 50*e^2 + 98, -64/15*e^5 + 886/15*e^3 - 2834/15*e, -14*e^4 + 182*e^2 - 544, 64/15*e^5 - 796/15*e^3 + 2324/15*e, -38/15*e^5 + 362/15*e^3 - 658/15*e, -4/5*e^5 + 86/5*e^3 - 344/5*e, 9*e^4 - 91*e^2 + 187, -2*e^2, 16*e^4 - 202*e^2 + 590, -17*e^4 + 213*e^2 - 631, -92/15*e^5 + 1238/15*e^3 - 3832/15*e, 22/5*e^5 - 288/5*e^3 + 947/5*e, 4*e^2 - 18, 56/15*e^5 - 764/15*e^3 + 2596/15*e, 86/15*e^5 - 1004/15*e^3 + 2701/15*e, 17*e^4 - 215*e^2 + 631, 2*e^4 - 2*e^2 - 82, 7/3*e^5 - 73/3*e^3 + 149/3*e, -2*e^4 + 44*e^2 - 178, 6*e^4 - 76*e^2 + 254, -1/3*e^5 + 25/3*e^3 - 89/3*e, -8*e^4 + 84*e^2 - 168, -4*e^4 + 66*e^2 - 244, 2*e^5 - 24*e^3 + 68*e, 8/5*e^5 - 82/5*e^3 + 103/5*e, 36/5*e^5 - 449/5*e^3 + 1321/5*e, 6*e^5 - 68*e^3 + 170*e, -4/5*e^5 + 66/5*e^3 - 174/5*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;