LMFDB definition
Bianchi newforms
A Bianchi newform is a Bianchi modular form lying in the new subspace of the space of Bianchi cusp forms of weight and level which is an normalised eigenform for the Hecke algebra .
For each prime of not dividing the level , the eigenvalue of on is an algebraic integer lying in the Hecke field of . This is a totally real Galois extension of whose degree is the dimension of the irreducible component of the rational newspace containing . The integer is the dimension of the newform . The Hecke eigenvalue is also the coefficient of index in the Fourier expansion of .
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