/* 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![29, 11, -10, -2, 1]; F := NumberField(g); ZF := Integers(F); NN := ideal; primesArray := [ [11, 11, -w - 1], [11, 11, w^2 - 5], [11, 11, -w^2 + 2*w + 4], [11, 11, w - 2], [16, 2, 2], [19, 19, w^2 - 2*w - 5], [19, 19, -w^2 + 6], [25, 5, -2*w^2 + 2*w + 11], [29, 29, w], [29, 29, 2*w^2 - w - 10], [29, 29, -2*w^2 + 3*w + 9], [29, 29, w - 1], [31, 31, w^3 - 6*w - 6], [31, 31, -w^3 + 3*w^2 + 3*w - 11], [41, 41, w^3 - 4*w^2 - 2*w + 16], [41, 41, w^3 - 5*w^2 - 2*w + 24], [59, 59, w^3 - w^2 - 5*w - 2], [59, 59, 2*w^2 - w - 13], [61, 61, w^3 - w^2 - 6*w + 3], [61, 61, -w^3 + 2*w^2 + 5*w - 3], [71, 71, 2*w^2 - w - 16], [71, 71, -w^3 + 3*w^2 + 4*w - 10], [71, 71, -w^3 + 7*w + 4], [71, 71, w^3 - 5*w^2 - 2*w + 23], [79, 79, -w^3 + 4*w^2 + 3*w - 16], [79, 79, w^3 + w^2 - 8*w - 10], [81, 3, -3], [131, 131, 4*w^2 - 5*w - 24], [131, 131, 4*w^2 - 3*w - 25], [139, 139, w^2 + w - 9], [139, 139, -w^3 + w^2 + 6*w - 5], [149, 149, w^3 - w^2 - 4*w + 2], [149, 149, w^3 - 2*w^2 - 3*w + 2], [151, 151, -w^3 + 7*w + 3], [151, 151, -w^3 + 3*w^2 + 4*w - 9], [179, 179, -w^3 - 2*w^2 + 10*w + 16], [179, 179, -w^3 + 3*w^2 + 3*w - 6], [179, 179, w^3 - 6*w - 1], [179, 179, w^3 - 5*w^2 - 3*w + 23], [191, 191, w^3 - 6*w^2 - w + 27], [191, 191, w^3 + 3*w^2 - 10*w - 21], [199, 199, -w^3 + 2*w^2 + 6*w - 4], [199, 199, -4*w^2 + 3*w + 22], [199, 199, 4*w^2 - 5*w - 21], [199, 199, 3*w^2 - 4*w - 12], [239, 239, -w^3 + w^2 + 4*w - 6], [239, 239, 2*w^3 - 5*w^2 - 9*w + 17], [239, 239, 2*w^3 - w^2 - 13*w - 5], [239, 239, w^3 - 8*w^2 + 2*w + 41], [241, 241, -w^3 + 5*w^2 + 4*w - 25], [241, 241, w^3 - 6*w - 8], [241, 241, -w^3 + 3*w^2 + 3*w - 13], [241, 241, w^3 - 5*w^2 + w + 19], [269, 269, w^2 - 2*w - 10], [269, 269, w^2 - 11], [271, 271, w^3 + 2*w^2 - 8*w - 18], [271, 271, 2*w^3 - 13*w - 10], [271, 271, 2*w^3 + w^2 - 15*w - 16], [271, 271, w^3 - 5*w^2 - w + 23], [289, 17, 2*w^2 - 11], [289, 17, -2*w^2 + 4*w + 9], [311, 311, w^3 - 4*w^2 - 3*w + 10], [311, 311, w^3 - 7*w^2 - w + 34], [331, 331, w^3 - w^2 - 7*w + 4], [331, 331, w^3 - 2*w^2 - 6*w + 3], [349, 349, w^3 + w^2 - 6*w - 12], [349, 349, -w^3 + 4*w^2 + w - 16], [361, 19, 4*w^2 - 4*w - 21], [379, 379, w^3 - 3*w^2 - 3*w + 15], [379, 379, 2*w^3 - 2*w^2 - 12*w + 1], [379, 379, -2*w^3 + 4*w^2 + 10*w - 11], [379, 379, w^3 - 6*w - 10], [401, 401, -2*w^3 + 7*w^2 + 8*w - 30], [401, 401, -w^3 + 2*w^2 + 6*w - 2], [419, 419, 5*w^2 - 4*w - 26], [419, 419, 5*w^2 - 6*w - 25], [421, 421, 3*w^2 - w - 20], [421, 421, -2*w^3 + 2*w^2 + 10*w + 3], [431, 431, w^2 - 3*w - 5], [431, 431, w^2 + w - 7], [449, 449, 2*w^3 - 13*w - 7], [449, 449, -2*w^3 + 6*w^2 + 7*w - 18], [461, 461, w^3 - w^2 - 8*w + 3], [461, 461, -w^3 + 2*w^2 + 7*w - 5], [491, 491, w^3 - 3*w^2 - 6*w + 15], [491, 491, w^3 - 9*w - 7], [499, 499, 4*w^2 - 6*w - 23], [499, 499, -4*w^2 + 2*w + 25], [509, 509, 2*w^3 - 3*w^2 - 11*w + 6], [521, 521, -w^3 + 3*w^2 + 2*w - 12], [521, 521, -w^3 + 4*w^2 + 2*w - 19], [529, 23, w^3 - 7*w^2 - w + 35], [529, 23, -w^3 + 3*w^2 + 4*w - 5], [541, 541, 2*w^3 - w^2 - 12*w - 5], [541, 541, w^3 - 2*w^2 - 7*w + 9], [569, 569, w^3 - 8*w - 2], [569, 569, -w^3 + 3*w^2 + 5*w - 9], [599, 599, -w^3 - 4*w^2 + 10*w + 25], [599, 599, -w^3 + 7*w^2 - 36], [601, 601, 5*w^2 - 6*w - 26], [601, 601, -2*w^3 + 8*w^2 + 6*w - 33], [601, 601, -2*w^3 - 2*w^2 + 16*w + 21], [601, 601, 5*w^2 - 4*w - 27], [619, 619, w^3 + 4*w^2 - 11*w - 26], [619, 619, w^3 - 3*w^2 - 5*w + 18], [641, 641, -w^3 + 3*w^2 + 6*w - 14], [641, 641, -w^3 + 9*w + 6], [659, 659, -w^3 - 4*w^2 + 10*w + 28], [659, 659, -w^3 + 6*w^2 - w - 27], [659, 659, -w^3 - 3*w^2 + 8*w + 23], [659, 659, -w^3 + 7*w^2 - w - 33], [691, 691, w^3 - w^2 - 8*w + 2], [691, 691, 2*w^3 - 2*w^2 - 11*w + 1], [701, 701, -w^3 - w^2 + 7*w + 15], [701, 701, -w^3 + 4*w^2 + 2*w - 20], [709, 709, -2*w^3 - w^2 + 15*w + 15], [709, 709, 2*w^3 - 7*w^2 - 7*w + 27], [719, 719, -w^3 - 4*w^2 + 13*w + 26], [719, 719, w^3 - 7*w^2 - 2*w + 34], [739, 739, 2*w^3 + 2*w^2 - 15*w - 24], [739, 739, -2*w^3 + 8*w^2 + 5*w - 35], [751, 751, -w^3 - 3*w^2 + 9*w + 25], [751, 751, -w^3 + 6*w^2 - 30], [761, 761, 3*w^3 - 2*w^2 - 16*w - 8], [761, 761, -3*w^3 + 7*w^2 + 11*w - 23], [769, 769, -2*w^3 + 4*w^2 + 11*w - 10], [769, 769, w^3 + 2*w^2 - 9*w - 12], [809, 809, -3*w^3 + 3*w^2 + 16*w + 4], [809, 809, w^3 + 5*w^2 - 12*w - 30], [811, 811, -w^3 - 4*w^2 + 10*w + 27], [811, 811, -2*w^3 + 5*w^2 + 9*w - 14], [811, 811, -2*w^3 + w^2 + 13*w + 2], [811, 811, -w^3 + 7*w^2 - w - 32], [821, 821, 2*w^3 - 8*w^2 - 7*w + 35], [821, 821, -2*w^3 - 2*w^2 + 17*w + 22], [829, 829, -3*w^3 + 20*w + 13], [829, 829, -w^3 + 7*w^2 - w - 36], [829, 829, w^3 + 4*w^2 - 10*w - 31], [829, 829, 2*w^3 - 3*w^2 - 11*w + 14], [859, 859, -w^3 + 7*w^2 - 3*w - 31], [859, 859, 7*w^2 - 9*w - 39], [859, 859, 7*w^2 - 5*w - 41], [859, 859, 3*w^3 - 4*w^2 - 17*w + 2], [929, 929, w^3 + 5*w^2 - 14*w - 31], [929, 929, -2*w^3 + 4*w^2 + 10*w - 5], [929, 929, w^3 - 9*w^2 + 4*w + 44], [929, 929, -w^3 + 8*w^2 + w - 39], [941, 941, -w^3 + 7*w^2 - 34], [941, 941, w^3 + 4*w^2 - 11*w - 28], [961, 31, -5*w^2 + 5*w + 28], [971, 971, -3*w^3 + w^2 + 19*w + 14], [971, 971, -3*w^3 + 8*w^2 + 12*w - 31], [991, 991, -w^3 - 5*w^2 + 11*w + 35], [991, 991, w^3 - 8*w^2 + 2*w + 40]]; primes := [ideal : I in primesArray]; heckePol := x^4 + 5*x^3 - 14*x^2 - 68*x + 8; K := NumberField(heckePol); heckeEigenvaluesArray := [1/4*e^2 + 1/4*e - 11/2, -3/16*e^3 - 9/16*e^2 + 11/4*e + 17/4, e, 1/8*e^3 + 3/8*e^2 - 3/2*e - 7/2, -1/16*e^3 + 1/16*e^2 + 1/2*e - 15/4, 1, -1/4*e^3 - 1/2*e^2 + 13/4*e + 7/2, 1/16*e^3 - 1/16*e^2 - 3/2*e + 3/4, 1/4*e^2 + 5/4*e - 5/2, 1/8*e^3 + 1/8*e^2 - 11/4*e - 1, -e - 3, 1/16*e^3 - 5/16*e^2 - 7/4*e - 3/4, -1/8*e^3 + 1/8*e^2 + 4*e + 1/2, 2, -1/16*e^3 + 9/16*e^2 - 43/4, 1/4*e^3 - 1/4*e^2 - 5*e + 4, 9/16*e^3 + 27/16*e^2 - 33/4*e - 51/4, -3/16*e^3 - 17/16*e^2 + 5/4*e + 29/4, 7/16*e^3 + 5/16*e^2 - 31/4*e + 15/4, 1/16*e^3 - 9/16*e^2 - e + 27/4, 1/16*e^3 - 5/16*e^2 - 15/4*e + 33/4, 3/8*e^3 + 5/8*e^2 - 6*e - 3/2, 9/16*e^3 + 19/16*e^2 - 31/4*e - 23/4, -3/16*e^3 - 1/16*e^2 + 21/4*e - 3/4, 7/16*e^3 + 5/16*e^2 - 35/4*e - 21/4, -1/8*e^3 + 5/8*e^2 + 7/2*e - 29/2, -1/8*e^3 - 3/8*e^2 + 5/2*e - 1/2, -3/4*e^3 - 9/4*e^2 + 11*e + 17, 1/2*e^2 + 5/2*e - 9, -7/8*e^3 - 5/8*e^2 + 33/2*e + 13/2, -3/2*e^2 - 7/2*e + 15, -1/2*e^3 - 7/4*e^2 + 19/4*e + 33/2, 7/16*e^3 + 9/16*e^2 - 15/2*e - 47/4, 1/2*e^3 + 3/2*e^2 - 8*e - 8, -9/16*e^3 - 19/16*e^2 + 27/4*e - 1/4, -13/16*e^3 - 23/16*e^2 + 53/4*e + 31/4, 7/8*e^3 + 21/8*e^2 - 25/2*e - 49/2, 3/4*e^3 + 2*e^2 - 45/4*e - 11/2, -3/8*e^3 - 5/8*e^2 + 7*e + 27/2, -1/4*e^3 - e^2 + 19/4*e - 7/2, -1/16*e^3 - 3/16*e^2 + 9/4*e + 43/4, e^2 + e - 10, -3/4*e^3 - 7/4*e^2 + 25/2*e + 10, -13/16*e^3 - 31/16*e^2 + 55/4*e + 91/4, -3/8*e^3 - 7/8*e^2 + 15/4*e + 7, -7/16*e^3 - 21/16*e^2 + 27/4*e + 21/4, -3/8*e^3 - 13/8*e^2 + 9*e + 39/2, 1/4*e^3 + 3/4*e^2 - 7*e - 13, 1/2*e^3 - 3/4*e^2 - 29/4*e + 55/2, 1/4*e^3 - 7/4*e^2 - 17/2*e + 21, 7/16*e^3 - 3/16*e^2 - 41/4*e - 13/4, -1/2*e^3 + 3/4*e^2 + 37/4*e - 41/2, e^3 + 9/4*e^2 - 67/4*e - 57/2, -7/16*e^3 - 5/16*e^2 + 39/4*e + 17/4, -9/16*e^3 - 31/16*e^2 + 3*e + 61/4, 1/8*e^3 - 11/8*e^2 - 13/4*e + 27, 5/4*e^3 + 2*e^2 - 79/4*e - 45/2, -1/4*e^3 - e^2 + 11/4*e - 3/2, 1/4*e^3 - 5/4*e^2 - 5*e + 29, -1/8*e^3 + 15/8*e^2 + 31/4*e - 27, -1/16*e^3 + 13/16*e^2 + 1/4*e - 105/4, 3/8*e^3 + 3/8*e^2 - 33/4*e - 6, -1/4*e^3 + 1/4*e^2 + 5*e - 15, -1/8*e^3 - 19/8*e^2 - 1/2*e + 43/2, -1/16*e^3 + 21/16*e^2 + 11/4*e - 25/4, 5/8*e^3 + 1/8*e^2 - 49/4*e - 10, 7/16*e^3 + 29/16*e^2 - 17/4*e - 37/4, 1/8*e^3 + 13/8*e^2 + 3/4*e - 20, 7/4*e^2 - 5/4*e - 73/2, -1/4*e^3 - 2*e^2 - 1/4*e + 21/2, -1/8*e^3 + 7/8*e^2 - 1/4*e - 28, 3/16*e^3 + 17/16*e^2 + 7/4*e - 5/4, 11/16*e^3 + 49/16*e^2 - 31/4*e - 125/4, 3/16*e^3 - 3/16*e^2 - 13/2*e + 101/4, -5/16*e^3 + 17/16*e^2 + 21/4*e - 89/4, -9/8*e^3 + 1/8*e^2 + 22*e - 11/2, 1/8*e^3 + 9/8*e^2 - 7/4*e - 21, 13/16*e^3 + 31/16*e^2 - 51/4*e - 71/4, 9/8*e^3 + 3/8*e^2 - 45/2*e - 15/2, -1/16*e^3 + 5/16*e^2 - 5/4*e - 57/4, 3/8*e^3 + 13/8*e^2 - 2*e - 73/2, -3/4*e^3 - 3/4*e^2 + 33/2*e - 3, -11/16*e^3 + 27/16*e^2 + 21/2*e - 165/4, -17/16*e^3 - 15/16*e^2 + 47/2*e + 41/4, -5/16*e^3 + 9/16*e^2 + 11/4*e - 117/4, 5/8*e^3 + 15/8*e^2 - 5/2*e - 35/2, -1/4*e^3 - 11/4*e^2 + 7*e + 33, 11/8*e^3 + 11/8*e^2 - 105/4*e - 14, 23/16*e^3 + 25/16*e^2 - 49/2*e - 75/4, 1/16*e^3 + 27/16*e^2 + 17/4*e - 107/4, 7/16*e^3 + 45/16*e^2 - 5/4*e - 93/4, 3/8*e^3 + 35/8*e^2 - 5/4*e - 37, -3/8*e^3 + 1/8*e^2 + 47/4*e + 16, -3/16*e^3 - 5/16*e^2 + 6*e - 49/4, -5/4*e^3 - 5/2*e^2 + 61/4*e + 21/2, -19/16*e^3 - 29/16*e^2 + 41/2*e + 103/4, 2*e^2 + e - 44, 19/16*e^3 + 49/16*e^2 - 93/4*e - 101/4, 5/16*e^3 + 23/16*e^2 - 15/4*e - 131/4, -1/2*e^3 + 2*e^2 + 15/2*e - 46, -11/16*e^3 - 45/16*e^2 + 10*e + 87/4, -5/16*e^3 - 7/16*e^2 + 19/4*e + 7/4, -1/4*e^3 - 3/4*e^2 + 11*e + 24, -1/8*e^3 + 5/8*e^2 + 15/2*e - 29/2, 27/16*e^3 + 65/16*e^2 - 91/4*e - 105/4, 15/16*e^3 + 9/16*e^2 - 21*e - 71/4, -11/16*e^3 + 3/16*e^2 + 11*e - 117/4, 5/8*e^3 + 7/8*e^2 - 35/2*e - 35/2, 2*e^3 + 2*e^2 - 39*e - 26, -13/8*e^3 - 23/8*e^2 + 53/2*e + 67/2, -21/16*e^3 - 55/16*e^2 + 87/4*e + 179/4, 7/8*e^3 + 21/8*e^2 - 23/2*e - 53/2, -1/8*e^3 + 21/8*e^2 + 19/2*e - 57/2, 11/8*e^3 + 41/8*e^2 - 35/2*e - 101/2, -3/2*e^3 - 9/2*e^2 + 22*e + 36, 3/16*e^3 - 11/16*e^2 - 2*e + 109/4, 15/16*e^3 + 81/16*e^2 - 27/2*e - 171/4, -3/2*e^3 - 5/2*e^2 + 23*e + 18, 1/4*e^3 - 1/4*e^2 - 12*e - 1, -3/8*e^3 + 7/8*e^2 + 21/2*e - 7/2, 9/8*e^3 + 11/8*e^2 - 31/2*e - 11/2, 7/8*e^3 + 9/8*e^2 - 15*e - 83/2, e^3 + e^2 - 11*e + 4, -13/8*e^3 - 31/8*e^2 + 45/2*e + 83/2, 1/16*e^3 + 7/16*e^2 + 6*e + 47/4, -e^3 - 3*e^2 + 20*e + 31, 3/8*e^3 + 15/8*e^2 - 7/4*e - 12, -5/8*e^3 + 7/8*e^2 + 29/4*e - 48, 17/16*e^3 + 51/16*e^2 - 49/4*e - 135/4, 23/16*e^3 + 29/16*e^2 - 97/4*e - 25/4, e^3 - 3/4*e^2 - 71/4*e + 25/2, -1/4*e^3 - 11/4*e^2 + 9*e + 33, -9/8*e^3 - 13/8*e^2 + 65/4*e - 9, -5/16*e^3 - 27/16*e^2 + 15/2*e + 29/4, -25/16*e^3 + 1/16*e^2 + 26*e - 139/4, -1/2*e^3 - 7/4*e^2 + 51/4*e + 69/2, -21/16*e^3 - 19/16*e^2 + 26*e + 5/4, 31/16*e^3 + 89/16*e^2 - 32*e - 175/4, -5/8*e^3 - 19/8*e^2 + 9*e + 75/2, -9/8*e^3 - 7/8*e^2 + 18*e - 7/2, 3/2*e^3 + 9/4*e^2 - 121/4*e - 49/2, 3/8*e^3 - 7/8*e^2 - 11/2*e + 43/2, -3/16*e^3 - 9/16*e^2 + 31/4*e - 71/4, -3/8*e^3 - 11/8*e^2 + 37/4*e + 25, 5/16*e^3 - 29/16*e^2 + 227/4, -1/2*e^3 + 7/2*e^2 + 19*e - 50, 1/16*e^3 - 13/16*e^2 + 11/4*e + 73/4, -13/16*e^3 + 29/16*e^2 + 41/2*e - 91/4, 5/16*e^3 - 13/16*e^2 - 12*e + 95/4, 3/4*e^3 + 3*e^2 - 9/4*e - 81/2, -13/8*e^3 - 27/8*e^2 + 17*e + 29/2, -3/2*e^3 - 3/4*e^2 + 135/4*e - 1/2, -7/4*e^3 - 1/2*e^2 + 127/4*e - 7/2, -e^3 - 3/4*e^2 + 57/4*e - 11/2]; 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;