According to others in this thread, it's

"\e", then "[", then "D"  ==eq==> "\x1B", "\x5B", "\x44"
"\e", then "[", then "C"  ==eq==> "\x1B", "\x5B", "\x45"
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(Each of the three values are returned by different calls to ReadKey.)

Based on what you said you have,

"\e[D\n" ==eq==> "\x1B\x5B\x44\x0A"
"\e[C\n" ==eq==> "\x1B\x5B\x45\x0A"
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Update: Fixed first half.