(sigma, tau)-superchampion numbers: numbers k for which there is a positive exponent e such that sigma(k)/(k*tau(k)^e) >= sigma(j)/(j*tau(j)^e) for all j >= 1, where tau(k) is the number of divisors of k (A000005) and sigma(k) is their sum (A000203).
A309811
(sigma, tau)-superchampion numbers: numbers k for which there is a positive exponent e such that sigma(k)/(k*tau(k)^e) >= sigma(j)/(j*tau(j)^e) for all j >= 1, where tau(k) is the number of divisors of k (A000005) and sigma(k) is their sum (A000203).
Terms
- a(0) =1a(1) =2a(2) =6a(3) =12a(4) =60a(5) =120a(6) =360a(7) =2520a(8) =5040a(9) =55440a(10) =720720a(11) =2162160a(12) =4324320a(13) =73513440a(14) =367567200a(15) =6983776800a(16) =160626866400a(17) =321253732800
External references
- oeis: A309811