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Question
Let < an > be a sequence. Write the first five term in the following:
a1 = a2 = 2, an = an − 1 − 1, n > 2
Solution
a1 = a2 = 2, an = an − 1 − 1, n > 2
\[a_3 = a_2 - 1 = 2 - 1 = 1\]
\[ a_4 = a_3 - 1 = 1 - 1 = 0\]
\[ a_5 = a_4 - 1 = 0 - 1 = - 1\]
Hence, the five terms are 2, 2, 1, 0 and \[-\]1 .
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