Matrix t*K(1) in Subspace 42 with Dimension 14

(K(1) is the first-order Grosse operator)

((I/2)*t)/Sqrt[3] ((13 + I*Sqrt[3])*U)/12 0 0 -((3*I + 2*Sqrt[3])*t)/(3*Sqrt[2]) 0 -((-3*I + Sqrt[3])*t)/(2*Sqrt[2]) ((-3*I + Sqrt[3])*t)/(6*Sqrt[2]) 0 (-I - 1/Sqrt[3])*t (1/Sqrt[2] - I/Sqrt[6])*t (Sqrt[2]*U + I*Sqrt[6]*U)/6 (I/2 + 1/Sqrt[3])*t ((3*I + Sqrt[3])*U)/4
(I/12)*(13*I + Sqrt[3])*U ((-I/2)*t)/Sqrt[3] ((3*I + Sqrt[3])*t)/6 0 0 (-Sqrt[2/3] + I/Sqrt[2])*t 0 0 -((3*I + 4*Sqrt[3])*t)/(3*Sqrt[2]) -((I + Sqrt[3])*U)/2 (Sqrt[2]*(1 - I*Sqrt[3])*U)/3 (1/Sqrt[2] + I/Sqrt[6])*t ((-3*I + Sqrt[3])*U)/12 ((-6*I + Sqrt[3])*t)/6
0 ((3*I - Sqrt[3])*t)/6 0 0 (-I)*Sqrt[6]*U ((1 + I*Sqrt[3])*t)/Sqrt[2] 0 0 0 0 0 -(Sqrt[2]*(-3*I + Sqrt[3])*t)/3 0 (I/2)*(I + Sqrt[3])*t
0 0 0 I*Sqrt[3]*t (-I/2)*(-3*I + Sqrt[3])*U 0 0 0 0 0 0 0 0 0
(Sqrt[2/3] - I/Sqrt[2])*t 0 (-I)*Sqrt[6]*U ((3 - I*Sqrt[3])*U)/2 0 0 (I/2)*(I + Sqrt[3])*t (I/2)*(I + Sqrt[3])*t 0 0 (I + 1/Sqrt[3])*t 0 I*Sqrt[3/2]*t 0
0 (Sqrt[2/3] + I/Sqrt[2])*t (I*(I + Sqrt[3])*t)/Sqrt[2] 0 0 0 (U - I*Sqrt[3]*U)/2 U t 0 0 (-I + 1/Sqrt[3])*t 0 t/Sqrt[2]
((3*I + Sqrt[3])*t)/(2*Sqrt[2]) 0 0 0 ((1 + I*Sqrt[3])*t)/2 (-U - I*Sqrt[3]*U)/2 0 t (U - I*Sqrt[3]*U)/2 Sqrt[2]*t 0 0 ((-I/2)*(-I + Sqrt[3])*t)/Sqrt[2] 0
-((3*I + Sqrt[3])*t)/(6*Sqrt[2]) 0 0 0 ((1 + I*Sqrt[3])*t)/2 -U -t 0 (U - I*Sqrt[3]*U)/2 ((-1 - I*Sqrt[3])*t)/Sqrt[2] (-I - 1/Sqrt[3])*t 0 ((-I/2)*(-I + Sqrt[3])*t)/Sqrt[2] 0
0 (2*Sqrt[2/3] - I/Sqrt[2])*t 0 0 0 -t (-U - I*Sqrt[3]*U)/2 (-U - I*Sqrt[3]*U)/2 0 0 0 (I - 1/Sqrt[3])*t 0 t/Sqrt[2]
(-I + 1/Sqrt[3])*t ((-I + Sqrt[3])*U)/2 0 0 0 0 -(Sqrt[2]*t) ((1 - I*Sqrt[3])*t)/Sqrt[2] 0 0 ((-I)/Sqrt[2] + 1/Sqrt[6])*t -(((-I + Sqrt[3])*U)/Sqrt[2]) 0 ((3 - I*Sqrt[3])*U)/2
(-(1/Sqrt[2]) - I/Sqrt[6])*t -(Sqrt[2]*(1 + I*Sqrt[3])*U)/3 0 0 (I - 1/Sqrt[3])*t 0 0 (-I + 1/Sqrt[3])*t 0 -((3*I + Sqrt[3])*t)/(3*Sqrt[2]) (I*t)/Sqrt[3] ((7 + I*Sqrt[3])*U)/6 ((-I)/Sqrt[2] + 1/Sqrt[6])*t 0
((I/3)*(I + Sqrt[3])*U)/Sqrt[2] (-(1/Sqrt[2]) + I/Sqrt[6])*t (Sqrt[2/3] + I*Sqrt[2])*t 0 0 (-I - 1/Sqrt[3])*t 0 0 (I + 1/Sqrt[3])*t ((I + Sqrt[3])*U)/Sqrt[2] (I/6)*(7*I + Sqrt[3])*U ((-I)*t)/Sqrt[3] ((-3*I + Sqrt[3])*U)/(3*Sqrt[2]) -((3*I + Sqrt[3])*t)/(3*Sqrt[2])
(I/2 - 1/Sqrt[3])*t -((3*I + Sqrt[3])*U)/12 0 0 I*Sqrt[3/2]*t 0 ((Sqrt[2] - I*Sqrt[6])*t)/4 ((Sqrt[2] - I*Sqrt[6])*t)/4 0 0 -((3*I + Sqrt[3])*t)/(3*Sqrt[2]) -((3*I + Sqrt[3])*U)/(3*Sqrt[2]) (I/2)*Sqrt[3]*t ((5 + I*Sqrt[3])*U)/4
-((-3*I + Sqrt[3])*U)/4 (-I - 1/(2*Sqrt[3]))*t ((1 + I*Sqrt[3])*t)/2 0 0 -(t/Sqrt[2]) 0 0 -(t/Sqrt[2]) (-I/2)*(-3*I + Sqrt[3])*U 0 ((-I)/Sqrt[2] + 1/Sqrt[6])*t (I/4)*(5*I + Sqrt[3])*U (I/2)*Sqrt[3]*t