Galois orbit label (reviewed)

The Galois orbits within each space of newforms $S^{\rm new}_k(N,[\chi])$ are labeled using small roman letters: $a, b, c, \ldots, z, aa, ba, \ldots$, with orbits ordered according to the lexicographical ordering of their integer trace sequences \[ ({\rm tr}_{K/\Q}(a_1),\ {\rm tr}_{K/\Q}(a_2), {\rm tr}_{K\Q}(a_3),\ \ldots) \] obtained by taking traces of Hecke eigenvalues $a_1,a_2,\ldots$ from the coefficient field $K$ down to $\Q$.