Maths Olympiad Prep

Library / CEMC Cayley /429 of 470

CEMC Cayley, 2005

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer Canada

The non-negative difference between two numbers aa and bb is a−ba - b or b−ab - a, whichever is greater than or equal to 0. For example, the non-negative difference between 24 and 64 is 40. In the sequence 88,24,64,40,24,…88, 24, 64, 40, 24, \ldots, each number after the second is obtained by finding the non-negative difference between the previous 2 numbers. The sum of the first 100 numbers in this sequence is

(A) 496496 (B) 760760 (C) 752752 (D) 776776 (E) 405405

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