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Question
Let < an > be a sequence. Write the first five term in the following:
a1 = 1 = a2, an = an − 1 + an − 2, n > 2
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Solution
a1 = 1 = a2, an = an − 1 + an − 2, n > 2
\[a_3 = a_2 + a_1 = 1 + 1 = 2\]
\[ a_4 = a_3 + a_2 = 2 + 1 = 3\]
\[ a_5 = a_4 + a_3 = 3 + 2 = 5\]
Hence, the five terms are 1, 1, 2, 3 and 5.
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