1729: Difference between revisions

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(Created page with "{{particular number}} ==Summary== ===Names=== This number is called the '''Hardy-Ramanujan number''' after a conversation between Hardy and Ramanujan where Ramanujan observ...")
 
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| [[Carmichael number]] || third among them || [[561]], [[1105]], [[1729]], ...
| [[Carmichael number]] || third among them || [[561]], [[1105]], [[1729]], ...
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|-
| [[Poulet number]] ([[Fermat pseudoprime to base 2) || sixth among them || [[341]], [[561]], [[645]], [[1105]], [[1387]], [[1729]], [[1905]], [[2047]]
| [[Poulet number]] ([[Fermat pseudoprime]] to base 2) || sixth among them || [[341]], [[561]], [[645]], [[1105]], [[1387]], [[1729]], [[1905]], [[2047]]
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Revision as of 20:29, 2 January 2012

This article is about a particular natural number.|View all articles on particular natural numbers

Summary

Names

This number is called the Hardy-Ramanujan number after a conversation between Hardy and Ramanujan where Ramanujan observed that it is the smallest number expressible as the sum of two cubes in two distinct ways: .

Factorization

Properties and families

Property or family Parameter values First few numbers
Carmichael number third among them 561, 1105, 1729, ...
Poulet number (Fermat pseudoprime to base 2) sixth among them 341, 561, 645, 1105, 1387, 1729, 1905, 2047