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 A134856 Numbers that can be written as (a^2-1)(b^2-1) in three or more distinct ways. 3
 2880, 27720, 40320, 49920, 63360, 98280, 241920, 282744, 491400, 547200, 604800, 950400, 970200, 1048320, 1370880, 1614600, 1774080, 2489760, 2608320, 2882880, 2923200, 3931200, 4817400, 6126120, 7338240, 7673400, 8426880, 10200960 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Contains A134857 and A134858 as subsequences. LINKS Table of n, a(n) for n=1..28. MathPages, Numbers Expressible As (a^2-1)(b^2-1). EXAMPLE 2880 = (2^2-1)(31^2-1) = (3^2-1)(19^2-1) = (5^2-1)(11^2-1). CROSSREFS Cf. A134857, A134858, A057535, A063066, A063067, A063068. Sequence in context: A175750 A179703 A260369 * A066407 A184602 A144547 Adjacent sequences: A134853 A134854 A134855 * A134857 A134858 A134859 KEYWORD easy,nonn AUTHOR Herman Beeksma, Nov 13 2007 STATUS approved

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Last modified June 23 07:33 EDT 2024. Contains 373629 sequences. (Running on oeis4.)