Did you mean: lcm %281 %2 C -1 %2 C zeta %2 C pi %29?
Y*l*m%281%2*C-1%2*C*theta%2*C*phi%29
solve(C*Mod(Mod(Y*l*m, 281), 2) - Mod(C*phi*Mod(C*theta, 2), 29), Y)
diff(C*Mod(Mod(Y*l*m, 281), 2) - Mod(C*phi*Mod(C*theta, 2), 29), Y)
series(C*Mod(Mod(Y*l*m, 281), 2) - Mod(C*phi*Mod(C*theta, 2), 29), Y, 0, 10)
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