22 lines
406 B
TeX
22 lines
406 B
TeX
\documentclass{article}
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\input{../../preamble}
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\begin{document}
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\begin{theorem}[Sum of Arithmetic Series]
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Let $(a_i)_{i \geq 0}$ be an arithmetic sequence with common difference $d$.
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Then for some $n \in \mathbb{N}$,
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$$\sum_{i=0}^n a_i = \frac{(n + 1)(a_0 + a_n)}{2}.$$
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\end{theorem}
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\begin{proof}
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\href{Arithmetic.lean}{Common.Sequence.Arithmetic.sum_recursive_closed}
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\end{proof}
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\end{document}
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