1. The problem is to find the first term in a Fibonacci-type sequence where the second term is 5 and the fifth term is 23.
2. Recall the Fibonacci-type sequence rule: each term is the sum of the two preceding terms.
3. Let the first term be $x$. Then the sequence terms are:
- First term: $x$
- Second term: 5
- Third term: $x + 5$
- Fourth term: $5 + (x + 5) = x + 10$
- Fifth term: $(x + 5) + (x + 10) = 2x + 15$
4. We know the fifth term is 23, so set up the equation:
$$2x + 15 = 23$$
5. Solve for $x$:
$$2x = 23 - 15$$
$$2x = 8$$
$$x = 4$$
6. Therefore, the first term is 4.
7. The sequence starts as: 4, 5, 9, 14, 23, ...
This satisfies the Fibonacci-type rule and the given terms.
Fibonacci First Term 4Caacc
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