Maths Olympiad Prep

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Number theory Difficulty 2.0 Junior Find the answer United Kingdom

The integers from 11 to 9999 are written in ascending order without spaces. The sequence of digits is then grouped into triples of digits: 123456789101112979899(123)(456)(789)(101)(112)(979)(899)123456789101112\ldots979899 \to (123)(456)(789)(101)(112)\ldots(979)(899). Which of the following is not one of the triples?

(A) (222)(222) (B) (434)(434) (C) (464)(464) (D) (777)(777) (E) (888)(888)

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