Let a0,b0,c0 be complex numbers, and define
an+1=an2+2bncn
bn+1=bn2+2cnan
cn+1=cn2+2anbn
for all nonnegative integers n.
Suppose that max∣an∣,∣bn∣,∣cn∣≤2022 for all n. Prove that
∣a0∣2+∣b0∣2+∣c0∣2≤1.
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