M_{12}.2

M_{11}  24 1a^{±} + 11ab  3

Character Numbers: [ 1, 2, 3 ]

S_{1} S_{2} S_{3}
χ_{1} 1 11 12
χ_{2} 1 11 −12
χ_{3} 1 −1  0

Ramanujan Graphs: [ 2 ], [ 2, 3 ], [ 3 ]