Question: Color Error in plot

restart:

with(plots):

equ1 := BesselJ(sqrt(17)/2, 10*sqrt(t)*sqrt(2))/t^(1/4) + BesselY(sqrt(17)/2, 10*sqrt(t)*sqrt(2))/t^(1/4):

equ2 := BesselJ(sqrt(17)/2, 10*sqrt(t)*sqrt(2))/t^(1/4) + 5*BesselY(sqrt(17)/2, 10*sqrt(t)*sqrt(2))/t^(1/4):

equ3 := BesselJ(sqrt(17)/2, 10*sqrt(t))/t^(1/4) + 5*BesselY(sqrt(17)/2, 10*sqrt(t))/t^(1/4):

tmax   := 30:
colors := ["Red", "Violet", "Blue"]:

p1 := plot([equ1, equ2, equ3], t = 0 .. tmax, labels = [t, T[2](t)], tickmarks = [0, 0], labelfont = [TIMES, ITALIC, 12], axes = boxed, color = colors):

ymin := min(op~(1, op~(2, op~(2, [plottools:-getdata(p1)])))):
ymax := max(op~(2, op~(2, op~(2, [plottools:-getdata(p1)])))):
dy   := 2*ymax:

legend1 := typeset(C[3] = 1, ` , `, C[4] = 1, ` , `, Omega^2 = 50):
legend2 := typeset(C[3] = 1, ` , `, C[4] = 5, ` , `, Omega^2 = 50):
legend3 := typeset(C[3] = 1, ` , `, C[4] = 5, ` , `, Omega^2 = 25):

p2 := seq(textplot([tmax-2, ymax-k*dy/20, legend||k], align=left), k=1..3):

p3 := seq(plot([[tmax-2, ymax-k*dy/20], [tmax-1, ymax-k*dy/20]], color=colors[k]), k=1..3):
display(p1, p2, p3, view=[default, -ymax..ymax], size=[800, 500])

Error, (in plot) invalid color specification: colors[1]