Equinumerous
Let 
and 
be two classes of Positive integers. Let 
be the number of integers in which are less than orequal to 
, and let 
be the number of integers in which are less than or equal to . Then if
and are said to be equinumerous. The four classes of Primes 
, 
, 
, 
are equinumerous. Similarly, since and are both ofthe form 
, and and are both of the form 
, and are also equinumerous.
References
Shanks, D. Solved and Unsolved Problems in Number Theory, 4th ed. New York: Chelsea, pp. 21-22 and 31-32, 1993.
- Cardioid
- Cardioid Caustic
- Cardioid Evolute
- Cardioid Inverse Curve
- Cardioid Involute
- Cardioid Pedal Curve
- Cards
- Carleman's Inequality
- Carlson-Levin Constant
- Carlson's Theorem
- Carlyle Circle
- Carmichael Condition
- Carmichael Function
- Carmichael Number
- Carmichael's Conjecture
- Carmichael Sequence
- Carmichael's Theorem
- Carmichael's Totient Function Conjecture
- Carnot's Polygon Theorem
- Carnot's Theorem
- Carotid-Kundalini Fractal
- Carotid-Kundalini Function
- Carry
- Carrying Capacity
- Cartan Matrix