A134856 Numbers that can be written as (a^2-1)(b^2-1) in three or more distinct ways.

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

Offset: 1

Author

Herman Beeksma, Nov 13 2007

Keywords

• easy
• nonn

Comments

Contains A134857 and A134858 as subsequences.

Examples

			2880 = (2^2-1)(31^2-1) = (3^2-1)(19^2-1) = (5^2-1)(11^2-1).
		

Links

• MathPages, Numbers Expressible As (a^2-1)(b^2-1).

Crossrefs

Cf. A134857, A134858, A057535, A063066, A063067, A063068.