/* 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, -3, -6, 0, 1]; F := NumberField(g); ZF := Integers(F); NN := ideal; primesArray := [ [3, 3, w], [5, 5, w - 1], [7, 7, w^3 - w^2 - 4*w + 1], [11, 11, -w^2 + w + 2], [13, 13, -w^3 + w^2 + 3*w - 1], [16, 2, 2], [17, 17, -w^3 + 5*w + 2], [29, 29, -w^2 + w + 1], [37, 37, -w^3 + 2*w^2 + 4*w - 4], [41, 41, -w^3 + w^2 + 5*w + 1], [41, 41, w^2 - 5], [47, 47, w^3 - w^2 - 5*w - 2], [47, 47, -w^3 + 2*w^2 + 4*w - 1], [53, 53, w^3 - 4*w - 4], [53, 53, 2*w^3 - 2*w^2 - 9*w + 1], [61, 61, -w^3 + w^2 + 6*w - 2], [71, 71, w^3 - w^2 - 6*w - 2], [103, 103, 2*w^3 - 2*w^2 - 8*w + 1], [103, 103, -3*w^3 + 3*w^2 + 13*w - 5], [109, 109, 2*w^3 - w^2 - 8*w - 4], [109, 109, 2*w^3 - w^2 - 9*w - 1], [113, 113, -2*w^3 + w^2 + 11*w - 1], [113, 113, 2*w^3 - w^2 - 10*w - 4], [125, 5, 2*w^3 - 3*w^2 - 10*w + 4], [131, 131, -2*w^3 + w^2 + 9*w - 1], [139, 139, 2*w^3 - 4*w^2 - 7*w + 5], [139, 139, 3*w^3 - w^2 - 16*w - 5], [149, 149, w^2 + w - 4], [149, 149, 3*w^3 - 3*w^2 - 13*w + 1], [151, 151, w^2 - 2*w - 8], [157, 157, w^3 - w^2 - 7*w - 2], [157, 157, -2*w^2 + w + 7], [167, 167, 2*w^3 - 2*w^2 - 7*w + 5], [173, 173, -w^3 + 6*w - 2], [173, 173, -w^3 + 2*w^2 + 5*w - 7], [181, 181, -3*w^3 + 2*w^2 + 14*w + 1], [191, 191, -w^3 + 2*w^2 + 2*w - 5], [191, 191, -w^3 + 2*w^2 + 6*w - 5], [193, 193, -w^3 + 3*w^2 + 4*w - 4], [193, 193, 2*w^3 + 3*w^2 - 13*w - 20], [197, 197, w^3 - 2*w - 2], [199, 199, 2*w^3 - w^2 - 11*w - 2], [211, 211, -2*w^3 + 9*w + 5], [223, 223, -w^3 + w^2 + 4*w - 5], [223, 223, w^2 - 3*w - 2], [229, 229, 2*w^3 - 2*w^2 - 7*w + 1], [241, 241, 3*w^2 - 2*w - 13], [241, 241, -w^3 + w^2 + 5*w + 4], [257, 257, -3*w^3 + w^2 + 15*w + 8], [263, 263, -3*w^3 + 5*w^2 + 9*w - 7], [263, 263, 2*w^3 - w^2 - 9*w + 2], [263, 263, -w^3 + 4*w^2 + 2*w - 16], [263, 263, w^3 - w^2 - 2*w - 2], [271, 271, -3*w - 1], [281, 281, 2*w^3 - 3*w^2 - 8*w + 2], [281, 281, 3*w^3 - 4*w^2 - 12*w + 4], [283, 283, w^3 - 5*w - 7], [293, 293, -2*w^3 + w^2 + 10*w - 1], [307, 307, w^3 - 3*w^2 - 3*w + 8], [307, 307, 3*w^3 - 15*w - 10], [311, 311, 2*w^3 - 3*w^2 - 7*w + 7], [313, 313, -w^3 + 7*w + 2], [337, 337, 3*w^3 - 17*w - 10], [337, 337, 2*w^3 - 2*w^2 - 9*w - 5], [343, 7, -2*w^3 + w^2 + 8*w + 2], [347, 347, -3*w^3 + 17*w + 14], [347, 347, -3*w^3 - w^2 + 17*w + 13], [349, 349, 2*w^3 - w^2 - 8*w - 1], [349, 349, -w^3 + 3*w^2 + 4*w - 8], [353, 353, -w^3 - w^2 + 7*w + 4], [359, 359, -2*w^3 + 9*w + 10], [367, 367, 3*w^3 - 4*w^2 - 9*w + 4], [367, 367, -w^3 + w^2 + 4*w + 4], [367, 367, -w^3 + 3*w^2 + 3*w - 7], [373, 373, -w^2 + w - 2], [373, 373, -2*w^3 + 2*w^2 + 11*w - 2], [379, 379, -2*w^3 + 4*w^2 + 7*w - 8], [379, 379, -w^2 - 2], [389, 389, -w^3 - 2*w^2 + 5*w + 11], [397, 397, -2*w^3 + 4*w^2 + 7*w - 7], [401, 401, w^3 - 3*w^2 - 2*w + 10], [401, 401, -2*w^3 + 11*w + 4], [401, 401, 3*w^3 - 2*w^2 - 14*w - 4], [401, 401, -3*w^3 + 4*w^2 + 15*w - 5], [421, 421, -w^3 + w^2 + 7*w - 1], [421, 421, -2*w^3 + 2*w^2 + 9*w - 7], [433, 433, w^2 - w - 8], [439, 439, -w^3 + 3*w^2 + 4*w - 7], [443, 443, -2*w^3 + w^2 + 10*w - 2], [449, 449, w^2 + 2*w - 4], [449, 449, 2*w^3 - 2*w^2 - 10*w - 1], [461, 461, 2*w^3 - 2*w^2 - 6*w + 5], [461, 461, -2*w^3 + 4*w^2 + 7*w - 13], [463, 463, -3*w^3 + 3*w^2 + 12*w - 4], [463, 463, w - 5], [467, 467, -3*w^3 + w^2 + 16*w + 8], [467, 467, 2*w^2 - 3*w - 10], [479, 479, 2*w^2 - 4*w - 1], [479, 479, -w^3 + 2*w^2 + 2*w - 7], [487, 487, -3*w^3 + 5*w^2 + 12*w - 10], [503, 503, w^3 + 2*w^2 - 8*w - 8], [509, 509, -3*w^3 + 5*w^2 + 11*w - 5], [521, 521, 2*w^2 - 3*w - 11], [523, 523, -2*w^3 - w^2 + 13*w + 11], [523, 523, -2*w^3 + 4*w^2 + 8*w - 7], [541, 541, 3*w^3 - 2*w^2 - 13*w + 1], [563, 563, w^3 - 3*w - 5], [563, 563, -w^3 + 3*w^2 + 2*w - 11], [569, 569, -2*w^3 + 4*w^2 + 9*w - 4], [569, 569, 3*w^2 - w - 14], [571, 571, -w^3 + 8*w - 1], [577, 577, 3*w^3 - 2*w^2 - 16*w + 1], [587, 587, -4*w^3 + 5*w^2 + 18*w - 7], [587, 587, 2*w^3 + w^2 - 10*w - 7], [599, 599, 2*w^3 + w^2 - 11*w - 8], [607, 607, w^3 - 3*w + 4], [613, 613, 3*w^3 - w^2 - 14*w - 5], [613, 613, 3*w^2 - w - 11], [619, 619, 2*w^2 - 5*w - 8], [631, 631, -2*w^3 - 2*w^2 + 12*w + 19], [647, 647, 2*w^3 - 2*w^2 - 11*w - 2], [653, 653, 3*w^3 - 5*w^2 - 8*w + 7], [677, 677, -2*w^3 + 4*w^2 + 5*w - 8], [683, 683, 2*w^3 + w^2 - 12*w - 8], [683, 683, -w^3 + 3*w^2 - 8], [683, 683, -2*w^3 + 3*w^2 + 11*w - 8], [683, 683, -2*w^3 + 3*w^2 + 10*w - 2], [691, 691, w^2 - 4*w - 1], [709, 709, 3*w^3 - 2*w^2 - 13*w - 2], [709, 709, w^3 - 2*w^2 - 3*w - 2], [727, 727, -w^3 + 4*w^2 + 2*w - 7], [727, 727, -w^3 + 8*w + 5], [733, 733, 3*w^2 - 2*w - 10], [733, 733, -w^3 + 5*w + 8], [757, 757, 3*w^3 - 14*w - 8], [761, 761, -w^3 + 3*w^2 + 5*w - 10], [773, 773, -2*w^3 + 3*w^2 + 9*w - 1], [787, 787, -w^3 + 4*w - 4], [797, 797, w^2 + 2*w - 5], [797, 797, w^3 + w^2 - 5*w - 1], [809, 809, w^3 + 3*w^2 - 9*w - 17], [811, 811, -4*w^2 + 3*w + 17], [811, 811, w^3 - 2*w^2 - 8*w + 2], [823, 823, -4*w^3 + 4*w^2 + 17*w - 4], [857, 857, 3*w^2 - w - 16], [881, 881, -2*w^3 + 9*w + 1], [883, 883, w^3 - w^2 - 4*w - 5], [887, 887, 3*w^2 + w - 10], [911, 911, w^3 - 3*w - 7], [919, 919, -w^3 + w^2 + 3*w - 7], [919, 919, 3*w^3 - 2*w^2 - 12*w + 2], [929, 929, 3*w^3 - w^2 - 16*w - 2], [929, 929, w^3 + w^2 - 6*w - 2], [941, 941, -3*w^3 + 5*w^2 + 14*w - 14], [941, 941, -w^3 + 2*w^2 + 6*w - 8], [947, 947, 3*w^3 - 3*w^2 - 13*w - 5], [947, 947, 3*w^3 - 4*w^2 - 12*w + 2], [953, 953, -3*w^3 + 5*w^2 + 10*w - 10], [961, 31, -w^3 + 4*w^2 + 3*w - 13], [961, 31, -4*w^3 + 3*w^2 + 17*w - 4], [967, 967, -w^3 - 4*w^2 + 9*w + 19], [967, 967, w^3 + 5*w^2 - 9*w - 26], [971, 971, -3*w^3 + 6*w^2 + 13*w - 7], [971, 971, w^3 + 2*w^2 - 7*w - 7], [977, 977, 2*w^3 - 3*w^2 - 4*w - 2], [983, 983, 3*w^3 - 5*w^2 - 7*w + 7], [991, 991, 2*w^2 - w - 13], [991, 991, w^3 - 8*w - 4]]; primes := [ideal : I in primesArray]; heckePol := x^6 - 28*x^4 + 213*x^2 - 236; K := NumberField(heckePol); heckeEigenvaluesArray := [2/5*e^4 - 29/5*e^2 + 32/5, e, -1, -1/5*e^5 + 17/5*e^3 - 46/5*e, -1/5*e^4 + 12/5*e^2 + 14/5, 1/5*e^4 - 17/5*e^2 + 41/5, -1/5*e^5 + 12/5*e^3 + 19/5*e, 1/5*e^5 - 12/5*e^3 - 19/5*e, 6/5*e^4 - 92/5*e^2 + 166/5, -1/5*e^5 + 17/5*e^3 - 41/5*e, -1/5*e^5 + 17/5*e^3 - 41/5*e, -2/5*e^5 + 29/5*e^3 - 32/5*e, -2/5*e^5 + 29/5*e^3 - 32/5*e, e, e, 6/5*e^4 - 92/5*e^2 + 126/5, 2/5*e^5 - 34/5*e^3 + 92/5*e, 7/5*e^4 - 104/5*e^2 + 152/5, 6/5*e^4 - 87/5*e^2 + 76/5, -4/5*e^4 + 63/5*e^2 - 94/5, 2/5*e^4 - 34/5*e^2 + 22/5, 1/5*e^5 - 22/5*e^3 + 91/5*e, -e^3 + 15*e, -3/5*e^5 + 46/5*e^3 - 83/5*e, -e^3 + 14*e, 2*e^2 - 12, 8/5*e^4 - 126/5*e^2 + 228/5, 4/5*e^5 - 63/5*e^3 + 129/5*e, 2/5*e^5 - 29/5*e^3 + 17/5*e, 2/5*e^4 - 29/5*e^2 + 52/5, -2/5*e^4 + 34/5*e^2 - 2/5, -e^4 + 16*e^2 - 42, 1/5*e^5 - 22/5*e^3 + 96/5*e, e^3 - 15*e, -1/5*e^5 + 22/5*e^3 - 91/5*e, -2/5*e^4 + 24/5*e^2 - 42/5, 0, 1/5*e^5 - 7/5*e^3 - 104/5*e, 2*e^4 - 30*e^2 + 42, -17/5*e^4 + 244/5*e^2 - 222/5, 1/5*e^5 - 12/5*e^3 - 39/5*e, -8/5*e^4 + 116/5*e^2 - 168/5, -2/5*e^4 + 24/5*e^2 - 12/5, -1/5*e^4 + 12/5*e^2 - 16/5, 12/5*e^4 - 184/5*e^2 + 272/5, -4/5*e^4 + 48/5*e^2 + 6/5, 2/5*e^4 - 34/5*e^2 + 82/5, 6/5*e^4 - 92/5*e^2 + 146/5, -2/5*e^5 + 29/5*e^3 - 37/5*e, 4*e, -4/5*e^5 + 68/5*e^3 - 204/5*e, 2/5*e^5 - 29/5*e^3 + 52/5*e, -2*e^3 + 28*e, 14/5*e^4 - 218/5*e^2 + 344/5, -1/5*e^5 + 7/5*e^3 + 79/5*e, 2/5*e^5 - 24/5*e^3 - 53/5*e, 8/5*e^4 - 106/5*e^2 - 12/5, 1/5*e^5 - 12/5*e^3 + 1/5*e, -6/5*e^4 + 97/5*e^2 - 136/5, 2/5*e^4 - 24/5*e^2 + 52/5, 2/5*e^5 - 34/5*e^3 + 92/5*e, 12/5*e^4 - 164/5*e^2 + 122/5, 12/5*e^4 - 194/5*e^2 + 402/5, 8/5*e^4 - 116/5*e^2 + 178/5, 12/5*e^4 - 174/5*e^2 + 192/5, 4/5*e^5 - 68/5*e^3 + 194/5*e, -1/5*e^5 + 17/5*e^3 - 86/5*e, 16/5*e^4 - 227/5*e^2 + 146/5, -12/5*e^4 + 184/5*e^2 - 202/5, -e^5 + 17*e^3 - 49*e, -3/5*e^5 + 41/5*e^3 - 28/5*e, -4*e^4 + 62*e^2 - 104, -8/5*e^4 + 96/5*e^2 + 32/5, 8/5*e^4 - 106/5*e^2 + 8/5, 24/5*e^4 - 358/5*e^2 + 494/5, -26/5*e^4 + 392/5*e^2 - 586/5, 7/5*e^4 - 124/5*e^2 + 252/5, -1/5*e^4 + 12/5*e^2 - 116/5, 1/5*e^5 - 22/5*e^3 + 121/5*e, -4/5*e^4 + 38/5*e^2 + 126/5, -1/5*e^5 + 12/5*e^3 + 19/5*e, -1/5*e^5 + 2/5*e^3 + 139/5*e, -2/5*e^5 + 24/5*e^3 + 23/5*e, -2/5*e^5 + 29/5*e^3 + 3/5*e, -8/5*e^4 + 131/5*e^2 - 278/5, -2/5*e^4 + 54/5*e^2 - 242/5, 8/5*e^4 - 126/5*e^2 + 298/5, 6/5*e^4 - 82/5*e^2 - 64/5, 10*e, e^5 - 16*e^3 + 39*e, -4/5*e^5 + 48/5*e^3 + 71/5*e, e^3 - 23*e, 4/5*e^5 - 63/5*e^3 + 149/5*e, -23/5*e^4 + 336/5*e^2 - 448/5, -3/5*e^4 + 36/5*e^2 + 32/5, -3/5*e^5 + 51/5*e^3 - 138/5*e, 2/5*e^5 - 24/5*e^3 - 58/5*e, -8*e, 3/5*e^5 - 46/5*e^3 + 108/5*e, 4/5*e^4 - 68/5*e^2 + 264/5, 2/5*e^5 - 24/5*e^3 - 28/5*e, -e^5 + 16*e^3 - 39*e, -6/5*e^5 + 92/5*e^3 - 141/5*e, 12/5*e^4 - 184/5*e^2 + 332/5, 4/5*e^4 - 58/5*e^2 + 84/5, -4*e^4 + 60*e^2 - 82, -3/5*e^5 + 51/5*e^3 - 138/5*e, 3/5*e^5 - 31/5*e^3 - 122/5*e, 3/5*e^5 - 56/5*e^3 + 223/5*e, 1/5*e^5 - 32/5*e^3 + 231/5*e, 16/5*e^4 - 242/5*e^2 + 276/5, 4/5*e^4 - 38/5*e^2 - 166/5, 3*e^3 - 30*e, 6/5*e^5 - 72/5*e^3 - 94/5*e, -2/5*e^5 + 39/5*e^3 - 172/5*e, 1/5*e^4 - 32/5*e^2 + 176/5, 30, -12/5*e^4 + 179/5*e^2 - 182/5, -2/5*e^4 + 49/5*e^2 - 112/5, -2/5*e^4 + 49/5*e^2 - 212/5, -1/5*e^5 + 22/5*e^3 - 136/5*e, 4/5*e^5 - 68/5*e^3 + 209/5*e, -3/5*e^5 + 46/5*e^3 - 63/5*e, -3*e^3 + 34*e, -6*e, 1/5*e^5 - 22/5*e^3 + 126/5*e, 3/5*e^5 - 51/5*e^3 + 98/5*e, -28/5*e^4 + 396/5*e^2 - 348/5, 16/5*e^4 - 222/5*e^2 + 166/5, -22/5*e^4 + 324/5*e^2 - 402/5, 6/5*e^4 - 77/5*e^2 - 44/5, 2*e^4 - 27*e^2 + 12, -34/5*e^4 + 498/5*e^2 - 554/5, 8/5*e^4 - 121/5*e^2 + 218/5, 2/5*e^4 - 44/5*e^2 + 222/5, 7/5*e^5 - 114/5*e^3 + 247/5*e, -e^5 + 16*e^3 - 27*e, -9/5*e^4 + 108/5*e^2 + 36/5, -3/5*e^5 + 31/5*e^3 + 77/5*e, -e^5 + 14*e^3 - 7*e, 1/5*e^5 - 12/5*e^3 - 9/5*e, -9/5*e^4 + 128/5*e^2 - 4/5, -4/5*e^4 + 48/5*e^2 + 156/5, 6/5*e^4 - 87/5*e^2 - 4/5, 1/5*e^5 - 2/5*e^3 - 89/5*e, 7/5*e^5 - 84/5*e^3 - 133/5*e, -22/5*e^4 + 329/5*e^2 - 552/5, 2/5*e^5 - 39/5*e^3 + 132/5*e, 3/5*e^5 - 46/5*e^3 + 108/5*e, e^4 - 12*e^2 - 40, 2*e^4 - 25*e^2 + 4, -3/5*e^5 + 46/5*e^3 - 133/5*e, e^5 - 14*e^3 + 15*e, 13/5*e^5 - 211/5*e^3 + 493/5*e, -1/5*e^5 + 32/5*e^3 - 251/5*e, -9/5*e^5 + 153/5*e^3 - 434/5*e, 4/5*e^5 - 78/5*e^3 + 334/5*e, 2*e^5 - 32*e^3 + 71*e, 2*e^4 - 30*e^2 + 18, 4*e^4 - 54*e^2 + 18, -4*e^4 + 60*e^2 - 88, 14/5*e^4 - 188/5*e^2 + 104/5, -8/5*e^5 + 131/5*e^3 - 318/5*e, -1/5*e^5 + 2/5*e^3 + 174/5*e, 3*e^3 - 41*e, 6/5*e^5 - 87/5*e^3 + 116/5*e, 18/5*e^4 - 296/5*e^2 + 608/5, 11/5*e^4 - 172/5*e^2 + 336/5]; 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;