a(n) = phi(5^n+1), where phi is Euler's totient function (A000010).
A366618
a(n) = phi(5^n+1), where phi is Euler's totient function (A000010).
Terms
- a(0) =1a(1) =2a(2) =12a(3) =36a(4) =312a(5) =1040a(6) =7200a(7) =25088a(8) =183808a(9) =557928a(10) =4396800a(11) =15333120a(12) =121680000a(13) =406812744a(14) =2817007200a(15) =8558784000a(16) =76264519680a(17) =254230063200
External references
- oeis: A366618