Carmichal number 561


561 is the smallest Carmichael numberMathworldPlanetmath in the ring of integersMathworldPlanetmath. However it is only a pseudoprime in the ring of Gaussian integersMathworldPlanetmath. We can use pari to find the bases to which 561 is a pseudoprime. I found it is pseudoprime to bases 12 + i, 22 +i, 34 + i and 56 + i. Needless to say it is a pseudoprime to other bases too. More on this later.

Title Carmichal number 561
Canonical name CarmichalNumber5611
Date of creation 2015-07-13 4:36:19
Last modified on 2015-07-13 4:36:19
Owner akdevaraj (13230)
Last modified by akdevaraj (13230)
Numerical id 2
Author akdevaraj (13230)
Entry type Definition