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function

a relationship between numbers where each number in the domain corresponds to exactly one number in the range

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sequence

a function whose domain is the set of all positive integers

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y=f(x)

formula for a sequence

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t sub n = t₁ + (n-1)d

explicit formula for an arithmetic sequence

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state a term; t sub n = t sub (n-1) +d

recursive formula for an arithmetic sequence

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t sub n = t₁ * rⁿ⁻¹

explicit formula for a geometric sequence

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state a term; t sub n = t sub (n-1) * r

recursive formula for a geometric sequence

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S sub n = n [(t₁ + t sub n)/2]

formula for the sum of the first n terms in an arithmetic sequence

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