The nth pentagonal number Pn follows the formula Pn = (3n² − n)/2 for positive integer n. For non-positive integer n, the same formula defines a generalized pentagonal number.
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The nth pentagonal number Pn follows the formula Pn = (3n² − n)/2 for positive integer n. For non-positive integer n, the same formula defines a generalized pentagonal number.
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Victor Shoup's "A Computational Introduction to Number Theory and Algebra" is a free online textbook covering number theory and algebra with a computational focus, suitable for advanced undergraduates and graduate students.
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A blog post discusses a mathematical identity where pentagonal numbers can be expressed in terms of triangular numbers. It highlights that while examples don't typically prove theorems, in this case the identity Pn = T(2n−1) − T(n−1) holds, showing that three examples can suffice for proving certain relationships.
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FineSet provides curated, quality-scored ML research datasets in JSONL format, sourced from ArXiv and Semantic Scholar papers, designed for training and evaluating machine learning models.
The nth pentagonal number Pn follows the formula Pn = (3n² − n)/2 for positive integer n. For non-positive integer n, the same formula defines a generalized pentagonal number.
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