Values of n such that (sigma(sigma(n))-phi(phi(n)))/n is an integer (the corresponding integral ratios are given in A136132).
A136131
Values of n such that (sigma(sigma(n))-phi(phi(n)))/n is an integer (the corresponding integral ratios are given in A136132).
Terms
- a(0) =1a(1) =3a(2) =5a(3) =18a(4) =32a(5) =36a(6) =92a(7) =144a(8) =368a(9) =576a(10) =712a(11) =800a(12) =888a(13) =918a(14) =928a(15) =1472a(16) =3193a(17) =4600a(18) =4768a(19) =8800a(20) =9288a(21) =10602a(22) =13032a(23) =16172a(24) =21204a(25) =26856a(26) =36864a(27) =56832a(28) =61792a(29) =84816
External references
- oeis: A136131