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Module 2: Mathematical Induction & Counting Techniques.

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The sequence 8,11,9,1,4,6,12,10,5,78, 11, 9, 1, 4, 6, 12, 10, 5, 7 contains 10 terms. Note that 10=32+110 = 3^2 + 1. There are four strictly increasing subsequences of length four, namely, 1,4,6,121, 4, 6, 12; 1,4,6,71, 4, 6, 7; 1,4,6,101, 4, 6, 10; and 1,4,5,71, 4, 5, 7. There is also a strictly decreasing subsequence of length four, namely, 11,9,6,511, 9, 6, 5.

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