Numbers k such that sigma(phi(k))/k > sigma(phi(m))/m for all m < k, where sigma is the sum of divisors function (A000203) and phi is Euler's totient function (A000010).
A293059
Numbers k such that sigma(phi(k))/k > sigma(phi(m))/m for all m < k, where sigma is the sum of divisors function (A000203) and phi is Euler's totient function (A000010).
Terms
- a(0) =1a(1) =5a(2) =7a(3) =13a(4) =31a(5) =37a(6) =61a(7) =181a(8) =241a(9) =421a(10) =899a(11) =1321a(12) =1333a(13) =1763a(14) =2161a(15) =2521a(16) =5183a(17) =7561a(18) =12601a(19) =15121a(20) =28187a(21) =30241a(22) =55441a(23) =110881a(24) =167137a(25) =278263a(26) =332641a(27) =555911a(28) =666917a(29) =722473
External references
- oeis: A293059