MHB Find the 79th term in the sequence

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The discussion focuses on finding the 79th term in the arithmetic sequence 7, -4, -1. The formula used is a_n = a_1 + (n-1)d, with a_1 set to -7 and d as -3. The calculation shows that a_{79} equals 227. A participant points out a typo in the formula, clarifying it should be a_n = a_1 + (n-1)d. The thread concludes with the corrected formula being acknowledged.
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Find the 79th term in the sequence - 7, - 4, - 1
$$a_n=a_1+\left(a_n-1 \right)d$$
$$n=79,\ \ a_1=-7, \ \ d=-3$$
$$a_{79}=-7+\left(79-1\right)\left(3\right)=227$$

I just followed an example?
 
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karush said:
Find the 79th term in the sequence - 7, - 4, - 1
$$a_n=a_1+\left(a_n-1 \right)d$$
$$n=79,\ \ a_1=-7, \ \ d=-3$$
$$a_{79}=-7+\left(79-1\right)\left(3\right)=227$$

I just followed an example?

There is a typo
$a_n=a_1+\left(n-1 \right)d$

rest is OK
 
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