Example 1 Let f = q + (−i − 1)q2 + (i − 1)q3 + O(q4 ) ∈ S2 Γ1(16)  and l = (5, i − 2). We catch ρf ,l in the 5-torsion of the Jacobian of X1(16) (genus 2). S = mfinit([16,2,0],1); f = mfeigenbasis(S[1])[1]; R = mfgalrep(f,[5,[[2,2]]],[30,50],5) factor(projgalrep(R)[1]) Nicolas Mascot p-adic computation of Galois representations