
# q-expansion of newform 847.2.a.m, downloaded from the LMFDB on 25 April 2024.

# We generate the q-expansion using the Hecke eigenvalues a_p at the primes.
# Each a_p is given as a linear combination
# of the following basis for the coefficient ring.

def make_data():

    from sage.all import prod, floor, prime_powers, gcd, QQ, primes_first_n, next_prime, RR

    def discrete_log(elts, gens, mod):
        # algorithm 2.2, page 16 of https://arxiv.org/abs/0903.2785
        def table_gens(gens, mod):
            T = [1]
            n = len(gens)
            r = [None]*n
            s = [None]*n
            for i in range(n):
                beta = gens[i]
                r[i] = 1
                N = len(T)
                while beta not in T:
                    for Tj in T[:N]:
                        T.append((beta*Tj) % mod)
                    beta = (beta*gens[i]) % mod
                    r[i] += 1
                s[i] = T.index(beta)
            return T, r, s
        T, r, s = table_gens(gens, mod)
        n = len(gens)
        N = [ prod(r[:j]) for j in range(n) ]
        Z = lambda s: [ (floor(s/N[j]) % r[j]) for j in range(n)]
        return [Z(T.index(elt % mod)) for elt in elts]
    def extend_multiplicatively(an):
        for pp in prime_powers(len(an)-1):
            for k in range(1, (len(an) - 1)//pp + 1):
                if gcd(k, pp) == 1:
                    an[pp*k] = an[pp]*an[k]
    from sage.all import PolynomialRing, NumberField, ZZ
    R = PolynomialRing(QQ, "x")
    f = R(poly_data)
    K = NumberField(f, "a")
    betas = [K([c/ZZ(den) for c in num]) for num, den in basis_data]
    convert_elt_to_field = lambda elt: sum(c*beta for c, beta in zip(elt, betas))
    # convert aps to K elements
    primes = primes_first_n(len(aps_data))
    good_primes = [p for p in primes if not p.divides(level)]
    aps = map(convert_elt_to_field, aps_data)
    if not hecke_ring_character_values:
        # trivial character
        char_values = dict(zip(good_primes, [1]*len(good_primes)))
    else:
        gens = [elt[0] for elt in hecke_ring_character_values]
        gens_values = [convert_elt_to_field(elt[1]) for elt in hecke_ring_character_values]
        char_values = dict([(
            p,prod(g**k for g, k in zip(gens_values, elt)))
            for p, elt in zip(good_primes, discrete_log(good_primes, gens, level))
            ])
    an_list_bound = next_prime(primes[-1])
    an = [0]*an_list_bound
    an[1] = 1
    
    from sage.all import PowerSeriesRing
    PS = PowerSeriesRing(K, "q")
    for p, ap in zip(primes, aps):
        if p.divides(level):
            euler_factor = [1, -ap]
        else:
            euler_factor = [1, -ap, p**(weight - 1) * char_values[p]]
        k = RR(an_list_bound).log(p).floor() + 1
        foo = (1/PS(euler_factor)).padded_list(k)
        for i in range(1, k):
            an[p**i] = foo[i]
    extend_multiplicatively(an)
    return PS(an)
level = 847
weight = 2
poly_data = [-2, -6, 7, 8, -5, -2, 1]

# The entries in the following list give a basis for the
# coefficient ring in terms of a root of the defining polynomial above.
# Each line consists of the coefficients of the numerator, and a denominator.
basis_data  = [[[1, 0, 0, 0, 0, 0], 1], [[0, 1, 0, 0, 0, 0], 1], [[-2, -1, 1, 0, 0, 0], 1], [[1, -3, -1, 1, 0, 0], 1], [[2, 2, -4, -1, 1, 0], 1], [[-2, 4, 6, -4, -2, 1], 1]]

hecke_ring_character_values = None
aps_data = [[-1, 1, 0, 0, 0, 0], [0, 0, 0, 0, 0, 1], [-1, 1, 1, 0, -1, 0], [-1, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0], [-1, 0, -1, 0, 1, -1], [-4, 1, 1, 1, 0, 0], [-1, -1, 0, 1, -2, -1], [1, -2, -1, -1, 3, 0], [-2, -1, -1, -1, 1, -1], [-1, 0, 1, -1, -2, -2], [4, -3, 2, 1, 1, 2], [-4, -1, 1, 1, -1, 0], [2, -3, 1, -2, 3, 1], [-3, 2, 3, -1, 2, 1], [0, 2, 1, 1, -3, 0], [-3, 4, -3, 3, 0, -3], [4, -6, -4, 2, 1, 2], [-1, 4, -1, 1, 1, -2], [4, 1, -1, 0, 0, 2], [-1, -1, 4, 1, 2, 3], [6, -3, -3, -2, -1, 1], [-3, -3, 0, -3, 2, -1], [0, -1, -4, -1, -3, -1], [-1, 3, 1, -2, 1, 2], [-7, 3, -4, -3, -3, -1], [-2, 0, -2, 2, -2, 1], [-1, 2, 3, -3, 1, -1], [-5, 4, -3, 0, 3, -1], [-3, 1, -1, 0, 4, 0], [-2, 2, -4, 2, -6, -4], [-6, -4, -2, 0, 0, -4], [4, 3, 3, 2, 0, -4], [7, 3, 4, -3, 0, 1], [-7, 3, 4, 0, 2, 0], [3, 6, 3, 5, -5, -3], [4, -2, -4, -2, -2, -2], [-1, -1, -2, -1, -3, 2], [-4, 4, 4, 2, 2, 6], [3, -3, 0, -1, -3, 7], [5, -3, 2, 5, -3, -4], [4, 1, -2, 7, 1, 2], [5, 3, 4, -3, -5, 4], [-1, 7, -2, -4, -2, 2], [-3, -4, 3, 0, -3, 3], [-13, -2, -5, -1, 2, -2], [2, -1, -1, 4, 3, -3], [-1, -4, 3, 5, -4, 3], [1, 3, -4, 9, -3, -3], [-8, -3, -6, 3, 3, 0], [-11, 0, 3, -4, -1, 1], [1, -1, 0, -1, -2, -4], [2, -6, 6, -4, 1, 6], [-5, 0, 1, -1, 0, -4], [-10, 3, -6, 1, -3, -5], [-8, 0, -4, 2, 2, 0], [0, -13, 2, 1, 1, 1], [-1, 5, -4, 5, -3, -1], [-3, -3, 6, -6, 8, 6], [-7, -2, 1, -3, 1, 1], [7, -1, 4, -3, 0, 7], [-14, 1, -3, -5, 1, 0], [-3, 7, -2, -5, 2, -3], [-1, 0, 3, 9, 0, 4], [-1, 1, 7, 2, -5, -3], [-1, 8, 1, 3, -3, -8], [-4, -2, 8, 2, 0, 6], [-8, -4, -8, -3, 2, 2], [-7, -2, -7, -1, -3, 1], [4, -3, 5, -11, 6, 6], [-4, -7, 2, -1, 1, 7], [8, -5, 5, 4, 1, 3], [2, 4, 4, 4, 2, -2], [8, -7, -5, 4, -1, -5], [8, 0, -2, 2, -6, 2], [-9, 0, -5, 1, -2, -8], [2, 3, 12, 1, -1, 4], [-9, 3, 7, 0, 5, -2], [-2, -7, 0, -1, -5, 2], [5, 2, -9, -4, -3, -9], [-8, -4, 0, 4, -4, 6], [-2, -1, 0, -11, 3, 2], [-7, 9, 6, 5, -10, -4], [-4, 5, 4, -3, -1, -7], [7, 5, 0, 5, -7, 1], [1, 0, 15, 5, 3, 4], [9, -5, -1, 6, 2, 6], [-10, -1, -5, 9, -9, -3], [-6, 1, 7, 5, 4, -2], [-7, 7, 6, 7, 3, 4], [5, -2, -11, -11, 6, -7], [5, -7, 0, -9, 10, 3], [-3, 3, -8, 1, 5, -6], [5, -3, 6, -1, 2, -4], [8, -1, -5, 6, 4, 8], [10, -8, -6, 2, 10, 4], [-6, -4, -14, -2, -2, -7], [7, -4, -5, -7, 0, 2], [4, 2, 8, 2, 5, 10], [-9, -4, 5, -1, -1, 3], [-8, 9, 7, -6, -1, 5], [-19, 6, 5, 1, -9, -1], [0, -2, -4, -8, 9, -2], [-12, -6, 2, 8, -8, 4], [9, 8, 7, -3, -3, 1], [-5, 9, 3, -6, 9, 8], [-7, -8, -17, -7, 14, 0], [-21, 8, -1, -6, -5, -9], [2, -12, -2, -2, 4, -6], [-7, 6, -1, 14, -9, -1], [12, -6, 4, 0, 9, 6], [18, -4, -6, 5, -6, -4], [-6, 9, -4, -5, 7, 2], [-10, 12, 4, 4, -10, -2], [-9, -1, -2, -1, -3, 0], [1, 12, 6, 10, -4, 0], [-7, 0, 1, -13, 4, 2], [6, -6, 16, -2, 2, 4], [11, -7, -16, -5, -1, -2], [-1, -4, -3, -5, 5, -7], [2, 5, -12, 9, -7, -5], [-8, 6, 14, 0, -2, -4], [9, 14, 5, 2, -6, -7], [2, -13, 7, 6, -4, 0], [-10, -4, -14, 2, -6, -10], [6, 9, -7, -3, 1, -3], [-2, -3, 11, 0, 10, 2], [-3, -8, 5, -9, 2, -2], [-4, 6, -6, 0, 0, 5], [-15, 10, -1, -8, -5, -3], [19, 5, -4, -9, 4, -8], [-1, 3, 6, 13, 0, 2], [16, 4, -8, 4, 8, 0], [-16, 5, 8, 3, -1, -2], [1, -8, -3, 12, -1, 9], [15, 10, 7, -2, -2, 3], [3, -6, -7, -3, 6, -14], [16, -12, -18, -2, 3, 2], [15, 0, 11, -11, 6, 8], [-1, -3, 0, 7, -6, -10], [-4, 4, 0, 2, 0, 6], [-5, -2, -13, -1, 13, 7], [10, 0, -4, -4, 18, -6], [-14, 4, 10, 8, -16, 4], [-8, 9, 6, 3, 1, -7], [-9, 6, -5, -9, 12, 4], [8, 1, 5, 3, 6, -8], [-29, 11, 6, 7, 5, -3], [11, -4, 9, -13, 4, 3], [23, -11, -4, 3, -5, 0], [-2, 8, 18, 15, -6, 12], [-17, -5, -5, 4, -1, -11], [5, 12, 19, -3, 1, -2], [-2, -4, -4, 4, 5, -2], [-23, 3, -14, -1, 5, -8], [-5, 7, -6, 3, -9, -8], [-11, 4, 3, 1, -9, 1], [-10, 15, -2, -3, -1, -8], [2, 3, 7, -9, 1, 8], [8, 5, 3, -13, -5, -2], [16, 12, 10, 10, -8, 6], [-8, -2, -14, 1, 10, 2], [15, 11, 2, 1, 0, 12], [-22, 2, 4, 10, -2, 8], [-15, 6, -6, 4, -4, -4], [-12, -2, 6, -4, -6, -7], [13, -20, 3, -11, 15, 14], [11, 2, 7, -6, -10, 5]]
