Sequences & Series

Arithmetic and geometric sequences and series formulas.

Arithmetic Sequence N-th Term

a_n = a_1 + (n-1)r

Sum of Arithmetic Sequence

S_n = \frac{a_1 + a_n}{2} \cdot n

Geometric Sequence N-th Term

a_n = a_1 \cdot q^{n-1}

Sum of Geometric Sequence

S_n = a_1 \frac{1-q^n}{1-q}

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